Joseph P. Colgan Margaret E. Berry David A. John 20241101 vector digital data https://doi.org/10.5066/P9WW1EUF David A. John Joseph P. Colgan Margaret E. Berry Christopher D. Henry Norman J. Silberling 2024 publication Scientific Investigations Map 3521 https://doi.org/10.3133/sim3521 This data set is a geospatial database for the 1:24,000 scale Geologic Map of the Southern Stillwater Range, Nevada (John and others, 2024). It contains all the geologic spatial information and text unit descriptions from the printed map, in the Geologic Map Schema (GeMS) format for digital geologic maps maintained by the USGS’ National Cooperative Geologic Mapping Program (NCMGP). Base map data are not included. When symbolized using the Federal Geographic Data Committee (FGDC) symbology for geologic maps, this database will closely approximate the appearance of the printed map. The purpose of this data set is to provide digital geospatial data for the Geologic Map of the Southern Stillwater Range, Nevada (John and others, 2024). It is not intended for use at scales more detailed than 1:24,000. Stillwater_24K_v3 is a composite geodataset that conforms to GeMS (Geologic Map Schema)--a standard format for the digital publication of geologic maps", available at http://ngmdb.usgs.gov/Info/standards/GeMS/. Metadata records associated with each element within the geodataset contain more detailed descriptions of their purposes, constituent entities, and attributes.). An OPEN shapefile versions of the dataset is also available. It consists of shapefiles, DBF files, and delimited text files and retains all information in the native geodatabase, but some programming will likely be necessary to assemble these components into usable formats. These metadata were prepared with the aid of script GeMS_FGDCMetadata.py, version of 2/27/24. 2024 publication date Complete None planned -118.4174 -118.1302 39.6898 39.3723 None geologic map Oligocene ignimbrite caldera USGS Metadata Identifier USGS:62102b0dd34e6c7e83bab258 None Nevada Churchill County Stillwater Range Dixie Valley None None Joseph P. Colgan U.S. Geological Survey mailing and physical

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Lakewood CO 80225 303-236-1021 Confidence that a feature exists and confidence that a feature is correctly identified are described in per-feature attributes ExistenceConfidence and IdentityConfidence. This data set is Level 3 GeMS valid using the October 2024 version of the GeMS validation script This data set contains all of the geologic information in the printed map. Base map data are not included. Estimated accuracy of horizontal location is given on a per-feature basis by attribute LocationConfidenceMeters. Values are expected to be correct within a factor of 2. A LocationConfidenceMeters value of -9 or -9999 indicates that no value has been assigned. Federal Geographic Data Committee 2006 publication https://ngmdb.usgs.gov/fgdc_gds/geolsymstd.php Digital and/or Hardcopy 2006 publication date FGDC-STD-013-2006 Standard vector and color symbols for geologic maps J.W. Bell T. Katzer 1987 publication https://ngmdb.usgs.gov/Prodesc/proddesc_26333.htm Digital and/or Hardcopy 1987 publication date BellKatzer1987 Geologic map data for compilation D.A. John N.J. Silberling 1994 publication Digital and/or Hardcopy 1994 publication date JohnSilberlingUnpub1994 Geologic map data for compilation D.A. John 1993 publication https://ngmdb.usgs.gov/Prodesc/proddesc_26453.htm Digital and/or Hardcopy 1993 publication date John1993 Geologic map data for compilation D.A. John 1992 publication https://ngmdb.usgs.gov/Prodesc/proddesc_5823.htm Digital and/or Hardcopy 1992 publication date John1992 Geologic map data for compilation D.A. John 1994 vector digital data Digital and/or Hardcopy 1994 observed JohnUnpub1994 Geologic map data for compilation D.A. John N.J. Silberling 1994 publication https://ngmdb.usgs.gov/Prodesc/proddesc_1215.htm Digital and/or Hardcopy 1994 publication date JohnSilberling1994 Geologic map data for compilation D.A. John 1995 publication https://ngmdb.usgs.gov/Prodesc/proddesc_26384.htm Digital and/or Hardcopy 1995 publication date John1995 Geologic map data for compilation W.M. Calvin J.W. Bell N.H. Hinx 2012 publication Digital and/or Hardcopy 2012 publication date CalvinOthers2012 Geologic map data for compilation M.R. Hudson D,A, John J.E. Conrad E.H. McKee 2000 publication https://doi.org/10.1029/1999JB900338 Digital and/or Hardcopy 2000 publication date HudsonOthers2000 Geochronologic data for geologic units in the map area J.P. Colgan D.A. John C.D. Henry K.E. Watts 2017 publication https://doi.org/10.5066/F7P26X2V Digital and/or Hardcopy 2017 publication date ColganOthers2017 Compilation of geochronology and geochemical data from the map area and surrounding area J.P. Colgan D.A. John C.D. Henry K.E. Watts 2018 publication https://doi.org/10.1016/j.jvolgeores.2017.10.015 Digital and/or Hardcopy 2018 publication date ColganOthers2018 Geochronologic and geochemical data for geologic units in the study area J.H. Stewart E.H. McKee D.A. John 1994 publication https://doi.org/10.3133/mf2154D Digital and/or Hardcopy 1994 publication date StewartOthers1994 Geochronologic data for geologic units in the map area C.D. Henry D.A. John 2013 publication https://doi.org/10.1130/GES00867.1 Digital and/or Hardcopy 2013 publication date HenryJohn2013 Geochronologic data for geologic units in the map area K.K.E. Neuendorf J.P. Mehl J.A. Jackson 2011 publication https://www.americangeosciences.org/pubs/glossary Digital and/or Hardcopy 2011 publication date AGI Definitions of geologic terms used in the database U.S. Geological Survey 2020 publication https://doi.org/10.3133/tm11B10 Digital and/or Hardcopy 2020 publication date GeMS Definition of the database format used by this database USGS Scientific Publications Network 2024 publication https://internal.usgs.gov/publishing/toolboxes/maptemplates/index.html Digital and/or Hardcopy 2024 publication date SPN Official USGS guidelines for geologic map cartographic layout D.A. John J.P. Colgan M.E. Berry C.D. Henry N.J. Silberling 2024 publication https://doi.org/10.3133/sim3521 Digital and/or Hardcopy 2024 publication date ThisReport Original publication from which this database is derived A preliminary digital database of this map was prepared from published geologic map data, unpublished mapping, and new fieldwork conducted by the authors. A preliminary cartographic representation of the data was then submitted for peer review of the scientific content. 2020 The geologic content of the database was revised following comments by peer reviewers and an updated cartographic version (PDF) derived from the database was submitted to the USGS for cartographic layout. 2022 The data were updated following review and changes by the USGS Scientific Publishing Network (SPN) map editors and officially approved for release by the USGS Bureau Approving Official 2024 A final version of the dataabase was prepared based on final version of the map publication. Metadata were generated and reviewed, and the data were released. 2024 Vector G-polygon 2034 Universal Transverse Mercator 11 0.9996 -117.0 0.0 500000.0 0.0 coordinate pair 0.6096 0.6096 meters D_North_American_1983 GRS_1980 6378137.0 298.257222101 DescriptionOfMapUnits Non-spatial table that captures content of the Description of Map Units (or equivalent List of Map Units and associated pamphlet text) included in a traditional paper geologic map. Has an internal hierarchy expressed by attribute HierarchyKey GeMS OBJECTID Internal feature number ESRI Unrepresentable domain MapUnit Short plain-text identifier of the map unit. Foreign key to DescriptionOfMapUnits table. GeMS Tor Older rhyolite John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet QTs Very old sediments John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tydai Dacite and andesite intrusions John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet TRcs Calcareous siltstone and sandstone of the Clan Alpine sequence John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Qao Old alluvial deposits John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Qlfo Older sediments of Lake Dixie John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tsd Silicic dikes John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tpcux Megabreccia blocks of underlying tuff and breccia of Government Trail Canyon and rhyolite of Pirouette Mountain John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Qam Young to Intermediate alluvial deposits John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet v Metavolcanic megabreccia within the tuff of Job Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tecx Megabreccia in tuff of Elevenmile Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet pa Blocks of propylitized andesite porphyry in tuff of Job Peak John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tjc Tuff of Job Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tlb Landslide breccia John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tpcu Upper cooling unit of tuff of Poco Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet JTRcl Upper limestone of the Clan Alpine sequence John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet s Argillite megabreccia within tuff of Elevenmile Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tgp Granite porphyry John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tpbr Tuff and breccia of Government Trail Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tdi Dacite intrusions John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Jq Middle and/or Lower Jurassic John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Kmd Dacitic volcanic-felsite flows and sedimentary breccia John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tfcgd Granodiorite porphyry John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tbi Basalt intrusions John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tfcgr Granite John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Trelc Rhyolite of East Lee Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tpsb Sandstone and breccia John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Qtc Talus, colluvium, and alluvium, undifferentiated John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tixl IXL pluton John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Td Diabase John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Qls Landslide deposits John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tolf Lava flows John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Jrmb Rhyolite megabreccia within tuff of Job Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tydat Dacite tuff John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet MZp Phyllite John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Todt Dacite tuff John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Qlbl Beach and shoreline deposits of Lake Lahontan John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Qay Young alluvial deposits John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tobr Breccia, conglomerate, and tuffs, undifferentiated John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Qes Eolian sand John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tddci Porphyritic dacite intrusions John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tec Tuff of Elevenmile Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Kmv Andesitic metavolcanic rocks John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tot Older tuffs, undifferentiated John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tha Hornblende andesite John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet TRca Argillite of the Clan Alpine sequence John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Qlf Sediments of Lake Dixie John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet ms Brecciated metashale and metasiltsone within the Tuff of Job Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tdg Diorite and granodiorite John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Qlb Beach and shoreline deposits of Lake Dixie John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Qbf Basin-fill deposits John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Alteration Hydrothermal alteration minerals John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Trpm Rhyolite of Pirouette Mountain John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tya Andesite John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet TRcl Lower limestone of the Clan Alpine sequence John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tyr Younger rhyolite John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tap Andesite porphyry John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Kms Metasedimentary rocks, undifferentiated John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Qlfl Sediments of Lake Lahontan John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tydas Lacustrine sedimentary rocks John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tjcx Megabreccia within the tuff of Job Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tjp Tuff of Job Peak John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Kf Felsite John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tupc Tuff of upper part of Poco Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet a Megabreccia blocks of Andesite of Sheep Canyon within tuff of Elevenmile Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tasc Andesite of Sheep Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tsi Silicic intrusive rocks John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tbs Basaltic sedimentary rocks John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet q Quartzite megabreccia within the tuff of Job Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tsf Silicic lava flows John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Qaya Main-stream alluvium John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tb Basalt John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tddc Dacite of Diamond Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Qai Intermediate alluvial deposits John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tpcl Lower cooling unit of tuff of Poco Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tyda Younger dacite and andesite unit, undivided John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Ts Sedimentary rocks, undifferentiated John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet m Marble megabreccia within tuff of Elevenmile Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet QTa Very old alluvial deposits John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Qtf Tufa deposits John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Trp Rhyolite porphyry John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tts Tuffs and sedimentary rocks John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet TRs Siltstone and argillite of the Clan Alpine sequence John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tst Sedimentary tuff John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tr Rhyolite John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Klp La Plata Canyon pluton John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Name Name of map unit, as shown in boldface in traditional DMU, e.g., "Shnabkaib Member". Identifies unit within its hierarchical context. GeMS Unrepresentable domain FullName Name of map unit including identification of containing higher rank unit(s), e.g., "Shnabkaib Member of Moenkopi Formation". GeMS Unrepresentable domain Age Age of map unit as shown in Description of Map Units. Examples of values are "late Holocene", "Pliocene and Miocene", "Lower Cretaceous". GeMS Unrepresentable domain Description Free-format text description of map unit. Commonly structured according to one or more accepted traditions (e.g., lithology, thickness, color, weathering and outcrop characteristics, distinguishing features, genesis, age constraints) and terse. GeMS Unrepresentable domain HierarchyKey String that records hierarchical structure. Has form nn-nn-nn, nnn-nnn, or similar. Numeric, left-padded with zeros, dash-delimited. Each HierarchyKey fragment of each row MUST be the same length to allow text-based sorting of table entries. GeMS Unrepresentable domain ParagraphStyle Token that identifies formatting of paragraph(s) within traditional Description of Map Units that correspond to this table entry. GeMS DMUUnit1 Paragraph style for description of a first-order map unit within Description of Map Units table. Times New Roman, Regular, 10 pt, 12 pt leading, left justified, 66 pt left indent, –20 pt 1st line indent, 3 pt space before. Map template distributed by USGS Scientific Publications Network, file MapStyleGuide_DMU_print_1sht_v1-1_01-15.pdf DMUHeading3 Heading style for third-order headings within Description of Map Units table. Times New Roman, Regular, 10 pt, 12 pt leading, all caps, centered, 10 pt space before. Map template distributed by USGS Scientific Publications Network, file MapStyleGuide_DMU_print_1sht_v1-1_01-15.pdf DMUHeading2 Heading style for second-order headings within Description of Map Units table. Such headings are subsidiary to the primary heading “Description of Map Units”. Times New Roman, bold, 10 pt, 12 pt leading, all caps, centered, 12 pt space before. Map template distributed by USGS Scientific Publications Network, file MapStyleGuide_DMU_print_1sht_v1-1_01-15.pdf Label Plain-text equivalent of the desired annotation for a feature: for example "14 Ma", or "^c" which (when used with the FGDC GeoAge font) results in the geologic map-unit label TRc (with TR run together to make the Triassic symbol). GeMS Unrepresentable domain Symbol Reference to a point marker, line symbol, or area-fill symbol that is used on the map graphic to denote the feature: perhaps a star for a K-Ar age locality, or a heavy black line for a fault. GeMS Unrepresentable domain AreaFillRGB {Red, Green, Blue} tuples that specify the suggested color (e.g., "255,255,255", "124,005,255") of area fill for symbolizing MapUnit. Each color value is an integer between 0 and 255, values are zero-padded to a length of 3 digits, and values are separated by commas with no space: NNN,NNN,NNN. GeMS Unrepresentable domain AreaFillPatternDescription Text description (e.g., "random small red dashes") provided as a convenience for users who must recreate symbolization. GeMS Unrepresentable domain DescriptionSourceID Source of map-unit description; foreign key to table Datasources. GeMS ThisReport John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet This report GeoMaterial Categorization of map unit based on lithologic and genetic character, term selected from NGMDB standard term list defined in Appendix A of GeMS documentation, available at http://ngmdb.usgs.gov/Info/standards/GeMS.. GeMS Colluvium and other widespread mass-movement sediment Sediment formed by slow, relatively widespread, downslope transport of particles or clasts produced by weathering and breakdown of underlying rock, sediment, and (or) soil. Composed of poorly sorted and poorly stratified material that ranges in size from clay to boulders. GeMS Fine-grained, mafic-composition intrusive igneous rock Rock that solidified from molten or partly molten material (magma) at shallow depth beneath Earths surface, thereby cooling quickly. Generally fine grained but may contain large mineral crystals (phenocrysts). Mostly found as tabular dikes or sills. Composed mostly of dark-colored minerals. Includes basaltic rock. GeMS Carbonate rock Sedimentary rock, consisting chiefly of carbonate minerals such as limestone or dolomite. GeMS Coarse-grained, felsic-composition intrusive igneous rock Rock that solidified from molten or partly molten material (magma) at some depth beneath Earths surface, thereby cooling slowly enough for mineral crystals to grow large enough to be visible to naked eye. Composed mostly of light-colored minerals (for example, feldspar, quartz). Includes granitic, syenitic, and monzonitic rock. GeMS Quartzite Rock derived from preexisting quartz-rich sedimentary rocks (commonly sandstone) and altered by essentially solid-state mineralogical, chemical, or structural changes, in response to marked changes in temperature, pressure, shear stress, and (or) chemical environment, generally at depth in Earths crust. GeMS Felsic-composition lava flows Lateral, surficial outpourings of molten lava from vent or fissure; also, solidified bodies of rock that form when they cool. Because of their high silica content and resulting high viscosity, parental magmas tend to erupt explosively, and so these deposits are uncommon. Includes fine-grained, light-colored rock with rhyolitic, dacitic, trachytic, and latitic composition. GeMS Lacustrine sediment, mostly coarse-grained Mostly well-sorted and well-bedded material, generally sand and gravel sized, with lesser amounts of silt and clay, deposited in perennial to intermittent lakes. Much of sediment is derived from material eroded and transported by streams. Mostly deposits of lake-marginal beaches and deltas. GeMS Mafic-composition lava flows Lateral, surficial outpourings of molten lava from vent or fissure; also, solidified bodies of rock that form when they cool. Low-silica parental magmas have low viscosity and tend to form extensive sheets that have generally low relief. Includes basaltic shield volcanoes, which may become very large (for example, in Hawaii). Composed of fine-grained, dark rocks, including basaltic. GeMS Debris flows, landslides, and other localized mass-movement sediment Sediment formed by relatively localized, downslope transport of particles or clasts produced by weathering and breakdown of underlying rock, sediment, and (or) soil. Composed of poorly sorted and poorly stratified material that ranges in size from clay to boulders. Speed of downslope transport ranges from rapid to imperceptible. GeMS Clastic sediment Sediment formed by weathering and erosion of preexisting rocks or minerals; eroded particles or clasts are transported and deposited by gravity, air, water, or ice. GeMS Volcaniclastic (fragmental) material Rock and unconsolidated material consisting of particles or clasts that were formed by volcanic explosion or aerial expulsion from volcanic vent. GeMS Intermediate-composition lava flows Lateral, surficial outpourings of molten lava from vent or fissure; also, solidified bodies of rock that form when they cool. Parental magma commonly erupts from stratovolcanoes as thick lava flows. Includes rocks that are, in color and in mineral composition, intermediate between felsic and mafic rocks (for example, andesite). GeMS Sand and gravel of unspecified origin Sediment composed mostly of sand and (or) gravel, formed by weathering and erosion of preexisting rocks or minerals; eroded particles or clasts are transported and deposited by gravity, air, water, or ice. GeMS Sandstone and mudstone Sandstone and mudstone (including shale and siltstone), in approximately equal (or unspecified) proportions. GeMS Lacustrine sediment, mostly fine-grained Mostly well-sorted and well-bedded material, generally silt and clay sized, with lesser amounts of sand, deposited in perennial to intermittent lakes. GeMS Fine-grained, felsic-composition intrusive igneous rock Rock that solidified from molten or partly molten material (magma) at shallow depth beneath Earths surface, thereby cooling quickly. Generally fine grained but may contain large mineral crystals (phenocrysts). Mostly found as tabular dikes or sills. Composed mostly of light-colored minerals. Includes rhyolitic, dacitic, trachytic, and latitic rock. GeMS Alluvial sediment, mostly coarse-grained Unconsolidated material deposited by streams or other bodies of running water as sorted or semisorted sediment in streambed, or on its floodplain or delta, or as cone or fan at base of mountain slope. Sediment is mostly sand, gravel, and coarser material but may also contain some silt and clay. GeMS Clastic sedimentary rock Sedimentary rock, composed predominantly of particles or clasts derived by erosion, weathering, or mass-wasting of preexisting rock and deposited by gravity, air, water, or ice. GeMS Other materials Other materials GeMS Felsic-composition pyroclastic flows Hot ash, pumice, and rock fragments erupted from volcano or caldera. Material moves downslope commonly in chaotic flows; once deposited, hot fragments may compact under their own weight and weld together. Because of their high-silica content and resulting high viscosity, parental magmas tend to erupt explosively. Includes rhyolite, dacite, trachyte, latite; rocks are commonly light-colored. GeMS Slate and phyllite, of sedimentary-rock origin Fine-grained rock derived from preexisting sedimentary rocks and altered by essentially solid-state mineralogical, chemical, or structural changes, in response to marked changes in temperature, pressure, deformation, and (or) chemical environment, generally at depth in Earths crust. Includes phyllite and slate (compact, fine-grained rock that possesses strong cleavage and, hence, can be split into slabs and thin plates). Mostly formed from fine-grained material such as mudstone. GeMS Alluvial sediment Unconsolidated material deposited by streams or other bodies of running water as sorted or semisorted sediment in streambed, or on its floodplain or delta, or as cone or fan at base of mountain slope. Grain size varies from clay to gravel. GeMS Meta-felsic and intermediate rock Rock derived from preexisting felsic and intermediate-composition rocks by essentially solid-state, mineralogical, chemical, or structural changes, in response to marked changes in temperature, pressure, deformation, and (or) chemical environment, generally at depth in Earths crust. Composed mostly of light-colored minerals; relatively enriched in silica. Includes metagranite, metadiorite, and meta-andesite. GeMS Sandstone Sedimentary rock, composed predominantly of particles or clasts derived by erosion and weathering of preexisting rock; consists mostly of sand-sized particles, with or without fine-grained matrix of silt or clay. GeMS Sedimentary and extrusive igneous material Either (1) sedimentary rock and (or) unconsolidated material (sediment) and extrusive igneous material (volcanic rock and [or] sediment) or (2) volcanic rock and (or) sediment and such material after erosion and redeposition. GeMS Dune sand Mostly sand-sized sediment, deposited by wind. Typically characterized by various dune landforms. GeMS Limestone Carbonate sedimentary rock, consisting chiefly of calcite. GeMS GeoMaterialConfidence Describes appropriateness of GeoMaterial term for describing the map unit. GeMS High The term and definition adequately characterize the overall lithologic nature of rocks and sediments in the map unit. Regarding the subjective term "adequately characterize", we refer to context and objectives of this classification as described in the GeMS documentation. GeMS documentation Medium The term and definition generally characterize the overall lithology of the map unit, but there are one or more significant minor lithologies that are not adequately described by the selected term. GeMS documentation Low The overall lithology of this map unit is not adequately classifiable using this list of terms and definitions, but the term selected is the best available. Or this map unit is insufficiently known to confidently assign a GeoMaterial term. GeMS documentation DescriptionOfMapUnits_ID Primary key. GeMS Arbitrary string. Values should be unique within this database. DataSources Non-spatial table of sources of all spatial features, sources of some attributes of spatial features, and sources of some attributes of non-spatial table entries. GeMS OBJECTID Internal feature number ESRI Unrepresentable domain Source Plain-text short description that identifies the data source. GeMS Unrepresentable domain Notes Additional information specific to a particular feature or table entry. GeMS Unrepresentable domain. Free text. Values of <null> or #null indicate no entry. URL Universal Resource Locator (URL) or Document Object Identifier (DOI), identifies a document on the World Wide Web. GeMS Unrepresentable domain DataSources_ID Primary key. GeMS Arbitrary string. Values should be unique within this database. Glossary Non-spatial table that, for certain fields (including all Type fields, Confidence fields, and GeneralLithology), lists the terms that populate these fields, term definitions, and sources for definitions. GeMS OBJECTID Internal feature number ESRI Unrepresentable domain Term Plain-language word for a concept. Values must be unique within database as a whole. GeMS Unrepresentable domain Definition Plain-language definition. GeMS Unrepresentable domain DefinitionSourceID Source of definition; foreign key to DataSources. GeMS FGDC-STD-013-2006 Federal Geographic Data Committee [prepared for the Federal Geographic Data Committee by the U.S. Geological Survey], 2006, FGDC Digital Cartographic Standard for Geologic Map Symbolization: Reston, Va., Federal Geographic Data Committee Document Number FGDC-STD-013-2006, 290 p., 2 plates. This report GeMS U.S. Geological Survey National Cooperative Geologic Mapping Program, 2020, GeMS (Geologic Map Schema)—A standard format for the digital publication of geologic maps: U.S. Geological Survey Techniques and Methods, book 11, chap. B10, 74 p., https://doi.org/10.3133/tm11B10. This report ThisReport John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet This report AGI Neuendorf, K.K.E., Mehl, J.P., Jr., and Jackson, J.A., eds., 2011, Glossary of Geology, Fifth Edition (revised): American Geosciences Institute, Alexandria, VA, 779 p. This report SPN Map template distributed by USGS Scientific Publications Network, file MapStyleGuide_DMU_print_1sht_v1-1_01-15.pdf This report Glossary_ID Primary key. GeMS Arbitrary string. Values should be unique within this database. GeoMaterialDict Non-spatial table that provides values of GeoMaterial, placed in a hierarchy, and their definitions. For further information, see Appendix A in GeMS documentation, available at http://ngmdb.usgs.gov/Info/standards/GeMS. GeMS OBJECTID Internal feature number ESRI Unrepresentable domain HierarchyKey String that records hierarchical structure. Has form nn-nn-nn, nnn-nnn, or similar. Numeric, left-padded with zeros, dash-delimited. Each HierarchyKey fragment of each row MUST be the same length to allow text-based sorting of table entries. GeMS Unrepresentable domain GeoMaterial Categorization of map unit based on lithologic and genetic character, term selected from NGMDB standard term list defined in Appendix A of GeMS documentation, available at http://ngmdb.usgs.gov/Info/standards/GeMS.. GeMS Loess Silty sediment, deposited by wind, commonly near glacial margin. GeMS Sedimentary rock Consolidated material (rock) composed of particles transported and deposited by gravity, air, water, or ice, or accumulated by other natural agents operating at Earths surface, such as chemical precipitation or secretion by organisms. Does not here include sedimentary material directly deposited as result of volcanic activity. GeMS Peat and muck Unconsolidated material, principally composed of plant remains, with lesser amounts of fine-grained clastic sediment. Deposited in water-saturated environment such as swamp, marsh, or bog. With lithification, such material becomes coal. GeMS Colluvium and other widespread mass-movement sediment Sediment formed by slow, relatively widespread, downslope transport of particles or clasts produced by weathering and breakdown of underlying rock, sediment, and (or) soil. Composed of poorly sorted and poorly stratified material that ranges in size from clay to boulders. GeMS Carbonate rock Sedimentary rock, consisting chiefly of carbonate minerals such as limestone or dolomite. GeMS Lacustrine sediment Mostly well-sorted and well-bedded material that ranges in grain size from clay to gravel, deposited in perennial to intermittent lakes. Much of sediment is derived from material eroded and transported by streams. Includes deposits of lake-marginal beaches and deltas. GeMS Lacustrine sediment, mostly coarse-grained Mostly well-sorted and well-bedded material, generally sand and gravel sized, with lesser amounts of silt and clay, deposited in perennial to intermittent lakes. Much of sediment is derived from material eroded and transported by streams. Mostly deposits of lake-marginal beaches and deltas. GeMS Mafic-composition lava flows Lateral, surficial outpourings of molten lava from vent or fissure; also, solidified bodies of rock that form when they cool. Low-silica parental magmas have low viscosity and tend to form extensive sheets that have generally low relief. Includes basaltic shield volcanoes, which may become very large (for example, in Hawaii). Composed of fine-grained, dark rocks, including basaltic. GeMS Intermediate-composition air-fall tephra Fragments of volcanic rock and lava, of various sizes, carried into the air by explosions and by hot gases in eruption columns or lava fountains; known as tephra. As tephra falls to ground, with increasing distance from volcano, average size of individual rock particles and thickness of resulting deposit decrease. Parental magma commonly erupts from stratovolcanoes as thick lava flows but also can generate strong explosive eruptions to form pyroclastic flows. Includes rocks that are, in color and mineral composition, intermediate between felsic and mafic rocks (for example, andesite). GeMS Igneous and metamorphic rock Consists of coarse-grained intrusive igneous rock and generally medium- to high-grade metamorphic rock. GeMS Intermediate-composition lava flows Lateral, surficial outpourings of molten lava from vent or fissure; also, solidified bodies of rock that form when they cool. Parental magma commonly erupts from stratovolcanoes as thick lava flows. Includes rocks that are, in color and in mineral composition, intermediate between felsic and mafic rocks (for example, andesite). GeMS Rock and sediment Various rocks and sediment, not differentiated. GeMS Extrusive igneous material Molten material that was erupted onto Earths surface, fusing into rock or remaining as unconsolidated particles. Includes pyroclastic flows, air-fall tephra, lava flows, and volcanic mass flows. GeMS Alluvial sediment, mostly coarse-grained Unconsolidated material deposited by streams or other bodies of running water as sorted or semisorted sediment in streambed, or on its floodplain or delta, or as cone or fan at base of mountain slope. Sediment is mostly sand, gravel, and coarser material but may also contain some silt and clay. GeMS Alluvial sediment, mostly fine-grained Unconsolidated material deposited by streams or other bodies of running water as sorted or semisorted sediment in streambed, or on its floodplain or delta, or as cone or fan at base of mountain slope. Sediment is mostly silt and clay but may also contain some sand and gravel. GeMS Igneous rock Rock and fragmental material that solidified from molten or partly molten material (magma). GeMS Alluvial sediment Unconsolidated material deposited by streams or other bodies of running water as sorted or semisorted sediment in streambed, or on its floodplain or delta, or as cone or fan at base of mountain slope. Grain size varies from clay to gravel. GeMS Sandstone Sedimentary rock, composed predominantly of particles or clasts derived by erosion and weathering of preexisting rock; consists mostly of sand-sized particles, with or without fine-grained matrix of silt or clay. GeMS Fine-grained intrusive igneous rock Rock that solidified from molten or partly molten material (magma) at shallow depth beneath Earths surface, thereby cooling quickly. Generally fine grained but may contain large mineral crystals (phenocrysts). Mostly found as tabular dikes or sills. GeMS Intermediate-composition pyroclastic flows Hot ash, pumice, and rock fragments erupted from volcano. Material moves downslope commonly in chaotic flows; once deposited, hot fragments may compact under their own weight and weld together. Parental magma commonly erupts from stratovolcanoes as thick lava flows but also can generate strong explosive eruptions to form pyroclastic flows. Includes rocks that are, in color and mineral composition, intermediate between felsic and mafic rocks (for example, andesite). GeMS Metamorphic rock Rock derived from preexisting rocks and altered by essentially solid-state mineralogical, chemical, or structural changes, in response to marked changes in temperature, pressure, deformation, and (or) chemical environment, generally at depth in Earths crust. GeMS Deformation-related metamorphic rock Rock derived from preexisting rocks by essentially solid-state mineralogical, chemical, or structural changes in response to strong deformation, commonly in association with marked changes in temperature, pressure, and (or) chemical environment. Generally forms in narrow, planar zones of local deformation (for example, along faults); characterized by foliation or alignment of mineral grains. Includes mylonite and cataclasite. GeMS Coarse-grained, mafic-composition intrusive igneous rock Rock that solidified from molten or partly molten material (magma) at some depth beneath Earths surface, thereby cooling slowly enough for mineral crystals to grow large enough to be visible to naked eye. Composed mostly of feldspar and dark-colored minerals. Includes gabbroic rock. GeMS Coastal zone sediment, mostly coarse-grained Mostly sand, silt, and gravel, deposited on beaches, in dunes, and in shallow-marine and related alluvial environments. GeMS Fine-grained, mafic-composition intrusive igneous rock Rock that solidified from molten or partly molten material (magma) at shallow depth beneath Earths surface, thereby cooling quickly. Generally fine grained but may contain large mineral crystals (phenocrysts). Mostly found as tabular dikes or sills. Composed mostly of dark-colored minerals. Includes basaltic rock. GeMS Meta-mafic rock Rock derived from preexisting mafic rocks by essentially solid-state, mineralogical, chemical, or structural changes, in response to marked changes in temperature, pressure, deformation, and (or) chemical environment, generally at depth in Earths crust. Composed mostly of iron- and magnesium-bearing, dark-colored and (or) green minerals. Includes greenstone, amphibolite, and metagabbro. GeMS Coarse-grained, felsic-composition intrusive igneous rock Rock that solidified from molten or partly molten material (magma) at some depth beneath Earths surface, thereby cooling slowly enough for mineral crystals to grow large enough to be visible to naked eye. Composed mostly of light-colored minerals (for example, feldspar, quartz). Includes granitic, syenitic, and monzonitic rock. GeMS Coarse-grained, intermediate-composition intrusive igneous rock Rock that solidified from molten or partly molten material (magma) at some depth beneath Earths surface, thereby cooling slowly enough for mineral crystals to grow large enough to be visible to naked eye. Intermediate in color and in mineral composition (between felsic and mafic igneous rock). Includes dioritic rock. GeMS Schist and gneiss, of sedimentary-rock origin Foliated rock derived from preexisting sedimentary rocks by essentially solid-state mineralogical, chemical, or structural changes in response to marked changes in temperature, pressure, deformation, and (or) chemical environment, generally at depth in Earths crust. Includes schist (characterized by such strong foliation or alignment of minerals that it readily splits into flakes or slabs) and gneiss (characterized by alternating, irregular bands of different mineral composition). Mostly formed from fine-grained material such as mudstone. GeMS Glacial till, mostly clayey Mostly unsorted and unstratified material, generally unconsolidated, deposited directly by and underneath or adjacent to glacier without subsequent reworking by meltwater. Consists of heterogeneous mixture of clay, silt, sand, gravel, and boulders, ranging widely in size and shape. Relatively clayey in texture. GeMS Intrusive igneous rock Rock that solidified from molten or partly molten material (magma) below Earths surface. GeMS Rock Various rock types, not differentiated. GeMS Quartzite Rock derived from preexisting quartz-rich sedimentary rocks (commonly sandstone) and altered by essentially solid-state mineralogical, chemical, or structural changes, in response to marked changes in temperature, pressure, shear stress, and (or) chemical environment, generally at depth in Earths crust. GeMS Felsic-composition lava flows Lateral, surficial outpourings of molten lava from vent or fissure; also, solidified bodies of rock that form when they cool. Because of their high silica content and resulting high viscosity, parental magmas tend to erupt explosively, and so these deposits are uncommon. Includes fine-grained, light-colored rock with rhyolitic, dacitic, trachytic, and latitic composition. GeMS Meta-volcaniclastic rock Rock derived from preexisting volcaniclastic rocks by essentially solid-state, mineralogical, chemical, or structural changes, in response to marked changes in temperature, pressure, deformation, and (or) chemical environment, generally at depth in Earths crust. Composed of deformed but recognizable particles or clasts of volcanic explosive material. GeMS Residual material Unconsolidated material, developed in place by weathering of underlying rock or sediment. Usually forms relatively thin surface layer that conceals unweathered or partly altered source material. Material from which soils are formed. GeMS Coarse-grained intrusive igneous rock Rock that solidified from molten or partly molten material (magma) at some depth beneath Earths surface, thereby cooling slowly enough for mineral crystals to grow large enough to be visible to naked eye. GeMS Meta-ultramafic rock Rock derived from preexisting ultramafic rocks by essentially solid-state, mineralogical, chemical, or structural changes, in response to marked changes in temperature, pressure, deformation, and (or) chemical environment, generally at depth in Earths crust. Composed mostly of magnesium-bearing minerals (for example, serpentine, talc, magnesite). GeMS Mafic-composition air-fall tephra Fragments of volcanic rock and lava, of various sizes, carried into the air by explosions and by hot gases in eruption columns or lava fountains; known as tephra. As tephra falls to ground, with increasing distance from volcano, average size of individual rock particles and thickness of resulting deposit decrease. Because of their low silica content and resulting low viscosity, parental magmas tend to erupt gently as lava flows, and so these deposits are uncommon. Includes basalt; rocks are commonly dark-colored. GeMS Evaporitic rock Sedimentary rock, composed primarily of minerals produced by evaporation of saline solution. Examples include gypsum, anhydrite, other diverse sulfates, halite (rock salt), primary dolomite, and rocks composed of various nitrates and borates. GeMS Sandstone and mudstone Sandstone and mudstone (including shale and siltstone), in approximately equal (or unspecified) proportions. GeMS Fine-grained, felsic-composition intrusive igneous rock Rock that solidified from molten or partly molten material (magma) at shallow depth beneath Earths surface, thereby cooling quickly. Generally fine grained but may contain large mineral crystals (phenocrysts). Mostly found as tabular dikes or sills. Composed mostly of light-colored minerals. Includes rhyolitic, dacitic, trachytic, and latitic rock. GeMS Mostly sandstone Mostly sandstone, interbedded with other sedimentary rocks that locally may include conglomerate and finer grained clastic rocks (mudstone), carbonates, and (or) coal. GeMS Other materials Other materials GeMS Slate and phyllite, of sedimentary-rock origin Fine-grained rock derived from preexisting sedimentary rocks and altered by essentially solid-state mineralogical, chemical, or structural changes, in response to marked changes in temperature, pressure, deformation, and (or) chemical environment, generally at depth in Earths crust. Includes phyllite and slate (compact, fine-grained rock that possesses strong cleavage and, hence, can be split into slabs and thin plates). Mostly formed from fine-grained material such as mudstone. GeMS Marine sediment Mud and sand, deposited in various marine environments. May originate from erosion of rocks and sediment or may be derived from marine organisms (of carbonate or siliceous composition). GeMS Eolian sediment Silt- and sand-sized sediment, deposited by wind. GeMS Coastal zone sediment Mud and sand, with lesser amounts of gravel, deposited on beaches, on barrier islands, or in nearshore-marine, deltaic, or various low-energy shoreline (mud flat, tidal flat, sabka, algal flat) environments. GeMS Metaigneous rock Rock derived from preexisting igneous rocks and altered by essentially solid-state, mineralogical, chemical, or structural changes, in response to marked changes in temperature, pressure, shear stress, and (or) chemical environment, generally at depth in Earths crust. GeMS Marine sediment, mostly coarse-grained Mud, sand, and gravel eroded from rocks and sediment on land, transported by streams, and deposited in marine deltas and basins. Mostly siliceous in composition. GeMS Ice-contact and ice-marginal sediment Mostly sand-, silt-, and gravel-sized particles or clasts derived from rock or preexisting sediment that has been eroded and transported by glaciers. As glacier melted, material was deposited by running water essentially in contact with glacial ice or was transported and deposited by glacially fed streams. Includes sediment deposited into water bodies adjacent to glacier. GeMS Felsic-composition air-fall tephra Fragments of volcanic rock and lava, of various sizes, carried into air by explosions and by hot gases in eruption columns or lava fountains; known as tephra. As tephra falls to ground, with increasing distance from volcano, average size of individual rock particles and thickness of resulting deposit decrease. Because of their high silica content and resulting high viscosity, felsic-composition magmas tend to erupt explosively, readily forming pumice and volcanic ash. Composed of light-colored rocks (for example, rhyolite, dacite, trachyte, latite). GeMS Metasedimentary rock Rock derived from preexisting sedimentary rocks and altered by essentially solid-state mineralogical, chemical, or structural changes, in response to marked changes in temperature, pressure, deformation, and (or) chemical environment, generally at depth in Earths crust. GeMS Mostly carbonate rock Mostly carbonate rock, interbedded with other sedimentary rock types. GeMS Contact-metamorphic rock Altered rock that originated by local processes of thermal metamorphism, genetically related to intrusion and extrusion of magmas and taking place at or near contact with body of igneous rock. Metamorphic changes are effected by heat and fluids emanating from magma and by some deformation because of emplacement of igneous mass. GeMS Volcanic mass flow Volcanic deposits formed by mass movement (for example, debris avalanches, debris flows, lahar deposits), in many cases triggered by volcanic eruption. Debris avalanches that occur on volcanoes clearly without eruptive trigger may be classified as sedimentary (for example, as Debris flows, landslides, and other localized mass-movement sediment). GeMS Exotic-composition intrusive igneous rock Rock that solidified from molten or partly molten material (magma) below Earths surface that has exotic mineralogical, textural, or field setting characteristics. Typically dark colored with abundant phenocrysts. Includes kimberlite, lamprophyre, lamproite, and foiditic rocks. GeMS Playa sediment Fine-grained clastic sediment and evaporitic salts, deposited in ephemeral lakes in centers of undrained basins. Includes material deposited in playas, mud flats, salt flats, and adjacent saline marshes. Generally interbedded with eolian sand and with lacustrine sediment deposited during wetter climatic periods; commonly intertongues upslope with sediment deposited by alluvial fans. GeMS Sedimentary material An aggregation of particles deposited by gravity, air, water, or ice, or as accumulated by other natural agents operating at Earths surface such as chemical precipitation or secretion by organisms. May include unconsolidated material (sediment) and (or) sedimentary rock. Does not include sedimentary material directly deposited as a result of volcanic activity. GeMS Medium and high-grade regional metamorphic rock, of unspecified origin Rock derived from preexisting rocks and altered by essentially solid-state mineralogical, chemical, or structural changes, in response to relatively intense regional changes in temperature, pressure, deformation, and (or) chemical environment, generally at depth in Earths crust. Origin of preexisting rock is mixed (for example, igneous and sedimentary) or is not known. Includes amphibolite, granulite, schist, and gneiss. GeMS Silt and clay of unspecified origin Sediment composed mostly of silt and (or) clay, formed by weathering and erosion of preexisting rocks or minerals; eroded particles or clasts are transported and deposited by gravity, air, water, or ice. GeMS Meta-carbonate rock Rock derived from preexisting carbonate sedimentary rocks and altered by essentially solid-state mineralogical, chemical, or structural changes, in response to marked changes in temperature, pressure, deformation, and (or) chemical environment, generally at depth in Earths crust. Characterized by recrystallization of carbonate minerals in source rock. Includes marble (for which preexisting rock was dominantly limestone or other rock composed of calcite), dolomitic marble, meta-dolostone, and meta-dolomite (for which preexisting rock contained appreciable amount of magnesium). GeMS Mass movement sediment Sediment formed by downslope transport of particles or clasts produced by weathering and breakdown of underlying rock, sediment, and (or) soil. Composed of poorly sorted and poorly stratified material that ranges in size from clay to boulders. Includes colluvial, landslide, talus, and rock-avalanche deposits. GeMS Unmapped area Unmapped area GeMS Water or ice Water or ice GeMS Debris flows, landslides, and other localized mass-movement sediment Sediment formed by relatively localized, downslope transport of particles or clasts produced by weathering and breakdown of underlying rock, sediment, and (or) soil. Composed of poorly sorted and poorly stratified material that ranges in size from clay to boulders. Speed of downslope transport ranges from rapid to imperceptible. GeMS Carbonate sediment Sediment formed by biotic or abiotic precipitation from aqueous solution of carbonates of calcium, magnesium, or iron (for example, limestone, dolomite). GeMS Chert Sedimentary rock, composed chiefly of microcrystalline or cryptocrystalline quartz. GeMS Volcaniclastic (fragmental) material Rock and unconsolidated material consisting of particles or clasts that were formed by volcanic explosion or aerial expulsion from volcanic vent. GeMS "Made" or human-engineered land Modern, unconsolidated material known to have human-related origin. GeMS Mudstone Sedimentary rock, composed predominantly of particles or clasts derived by erosion and weathering of preexisting rock; consists mostly of mud (that is, silt- and clay-sized particles). Includes shale and siltstone. GeMS Felsic-composition pyroclastic flows Hot ash, pumice, and rock fragments erupted from volcano or caldera. Material moves downslope commonly in chaotic flows; once deposited, hot fragments may compact under their own weight and weld together. Because of their high-silica content and resulting high viscosity, parental magmas tend to erupt explosively. Includes rhyolite, dacite, trachyte, latite; rocks are commonly light-colored. GeMS Mostly mudstone Mostly mudstone, interbedded with other sedimentary rocks that locally may include coarser grained clastic rocks (sandstone, conglomerate), carbonates, and (or) coal. GeMS Meta-felsic and intermediate rock Rock derived from preexisting felsic and intermediate-composition rocks by essentially solid-state, mineralogical, chemical, or structural changes, in response to marked changes in temperature, pressure, deformation, and (or) chemical environment, generally at depth in Earths crust. Composed mostly of light-colored minerals; relatively enriched in silica. Includes metagranite, metadiorite, and meta-andesite. GeMS Sediment Unconsolidated material (sediment) composed of particles deposited by gravity, air, water, or ice, or as accumulated by other natural agents operating at Earths surface such as chemical precipitation or secretion by organisms. Does not include sedimentary material directly deposited as a result of volcanic activity. GeMS Ice-contact and ice-marginal sediment, mostly coarse-grained Mostly sand- and gravel-sized particles or clasts, with lesser amounts of silt and clay, derived from rock or preexisting sediment that has been eroded and transported by glaciers. As glacier melted, material was deposited by running water essentially in contact with glacial ice or was transported and deposited by glacially fed streams. Includes sediment deposited into water bodies adjacent to glacier. GeMS Sedimentary and extrusive igneous material Either (1) sedimentary rock and (or) unconsolidated material (sediment) and extrusive igneous material (volcanic rock and [or] sediment) or (2) volcanic rock and (or) sediment and such material after erosion and redeposition. GeMS Ice-contact and ice-marginal sediment, mostly fine-grained Mostly silt- and clay-sized particles or clasts, with lesser amounts of sand and gravel, derived from rock or preexisting sediment that has been eroded and transported by glaciers. As glacier melted, material was deposited by running water essentially in contact with glacial ice or was transported and deposited by glacially fed streams. Includes sediment deposited into water bodies adjacent to glacier. GeMS Dune sand Mostly sand-sized sediment, deposited by wind. Typically characterized by various dune landforms. GeMS Limestone Carbonate sedimentary rock, consisting chiefly of calcite. GeMS Regional metamorphic rock, of unspecified origin Rock derived from preexisting rocks and altered by essentially solid-state mineralogical, chemical, or structural changes, in response to marked regional changes in temperature, pressure, deformation, and (or) chemical environment, generally at depth in Earths crust. Origin of preexisting rock is mixed (for example, igneous and sedimentary) or is not known. GeMS Air-fall tephra Fragments of volcanic rock and lava, of various sizes, carried into air by explosions and by hot gases in eruption columns or lava fountains; known as tephra. As tephra falls to ground, with increasing distance from volcano, average size of individual rock particles and thickness of resulting deposit decrease. Fine tephra deposited at some distance from volcano is known as volcanic ash. GeMS Lower-grade metamorphic rock, of unspecified origin Rock derived from preexisting rocks and altered by essentially solid-state mineralogical, chemical, or structural changes, in response to relatively mild regional changes in temperature, pressure, deformation, and (or) chemical environment, generally at depth in Earths crust. Origin of preexisting rock is mixed (for example, igneous and sedimentary) or is not known. Includes slate and phyllite. GeMS Coastal zone sediment, mostly fine-grained Mostly clay and silt, deposited in lagoons, tidal flats, backbarriers, and coastal marshes. GeMS Pyroclastic flows Hot ash, pumice, and rock fragments erupted from volcano or caldera. Material moves downslope commonly in chaotic flows; once deposited, hot fragments may compact under their own weight and weld together. GeMS Marine sediment, mostly fine-grained Mostly clay- and silt-sized sediment, deposited in relatively deep, quiet water, far removed from areas where coarser grained clastic sediments are washed into marine environment. Includes sediment derived from marine organisms. GeMS Conglomerate Sedimentary rock, composed predominantly of particles or clasts derived by erosion and weathering of preexisting rock; contains more than 30 percent gravel-sized clasts. GeMS Mafic-composition pyroclastic flows Hot ash, pumice, and rock fragments erupted from volcano. Material moves downslope commonly in chaotic flows; once deposited, hot fragments may compact under their own weight and weld together. Because of their low silica content and resulting low viscosity, parental magmas tend to erupt gently as lava flows rather than more forcefully as pyroclastic flows. Includes basalt; rocks are commonly dark-colored. GeMS Glacial till Mostly unsorted and unstratified material, generally unconsolidated, deposited directly by and underneath or adjacent to glacier without subsequent reworking by meltwater. Consists of heterogeneous mixture of clay, silt, sand, gravel, and boulders, ranging widely in size and shape. GeMS Fine-grained, intermediate-composition intrusive igneous rock Rock that solidified from molten or partly molten material (magma) at shallow depth beneath Earths surface, thereby cooling quickly. Generally fine grained but may contain large mineral crystals (phenocrysts). Mostly found as tabular dikes or sills. Intermediate in color and in mineral composition (between felsic and mafic igneous rock). Includes andesitic rock. GeMS Ultramafic intrusive igneous rock Rock that solidified from molten or partly molten material (magma) at some depth beneath Earths surface, thereby cooling slowly enough for mineral crystals to grow large enough to be visible to naked eye. Composed almost entirely of mafic minerals (for example, hypersthene, augite, olivine). GeMS Clastic sediment Sediment formed by weathering and erosion of preexisting rocks or minerals; eroded particles or clasts are transported and deposited by gravity, air, water, or ice. GeMS Coal and lignite Organic-rich sedimentary rock, formed from compaction and alteration of plant remains. Coal is consolidated, harder, black rock. Lignite is semiconsolidated, brown to black, earthy material that may contain large particles of recognizable plant parts and tends to crack upon drying. GeMS Sand and gravel of unspecified origin Sediment composed mostly of sand and (or) gravel, formed by weathering and erosion of preexisting rocks or minerals; eroded particles or clasts are transported and deposited by gravity, air, water, or ice. GeMS Lacustrine sediment, mostly fine-grained Mostly well-sorted and well-bedded material, generally silt and clay sized, with lesser amounts of sand, deposited in perennial to intermittent lakes. GeMS Glacial till, mostly sandy Mostly unsorted and unstratified material, generally unconsolidated, deposited directly by and underneath or adjacent to glacier without subsequent reworking by meltwater. Consists of heterogeneous mixture of clay, silt, sand, gravel, and boulders, ranging widely in size and shape. Relatively sandy in texture. GeMS Clastic sedimentary rock Sedimentary rock, composed predominantly of particles or clasts derived by erosion, weathering, or mass-wasting of preexisting rock and deposited by gravity, air, water, or ice. GeMS Glacial till, mostly silty Mostly unsorted and unstratified material, generally unconsolidated, deposited directly by and underneath or adjacent to glacier without subsequent reworking by meltwater. Consists of heterogeneous mixture of clay, silt, sand, gravel, and boulders, ranging widely in size and shape. Relatively loamy (silty) in texture. GeMS Iron-rich sedimentary rock Sedimentary rock, in which at least half (by volume) of observed minerals are iron bearing (hematite, magnetite, limonite group minerals, siderite, iron sulfides). GeMS Lava flows Lateral, surficial outpourings of molten lava from vent or fissure; also, solidified bodies of rock that form when they cool. Composed generally of fine-grained, dark-colored rocks (for example, basalt), which tend to form extensive sheets that have generally low relief, except in vent areas where cinder cones or shield volcanoes may form. Includes basaltic shield volcanoes, which may become very large (for example, Hawaii). GeMS Dolomite Carbonate sedimentary rock, consisting chiefly of dolomite. Although dolostone is the proper analog to limestone, it has not often been applied to dolomitic units. GeMS IndentedName Name with addition of leading spaces to help show rank within a hierarchical list. GeMS Unrepresentable domain Definition Plain-language definition. GeMS Unrepresentable domain MapUnitPolys Polygons that record distribution of map units (including water, snowfields, glaciers, and unmapped area) on the particular map horizon. In the original file geodatabase, this dataset is found within the GeologicMap feature dataset. GeMS OBJECTID Internal feature number ESRI Unrepresentable domain Shape Internal geometry object ESRI Unrepresentable domain Shape_Length Internal feature length, double ESRI Unrepresentable domain Shape_Area Internal feature area, double ESRI Unrepresentable domain MapUnit Short plain-text identifier of the map unit. Foreign key to DescriptionOfMapUnits table. GeMS Tor Older rhyolite John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet QTs Very old sediments John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tydai Dacite and andesite intrusions John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet TRcs Calcareous siltstone and sandstone of the Clan Alpine sequence John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Qao Old alluvial deposits John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Qlfo Older sediments of Lake Dixie John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tsd Silicic dikes John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tpcux Megabreccia blocks of underlying tuff and breccia of Government Trail Canyon and rhyolite of Pirouette Mountain John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Qam Young to Intermediate alluvial deposits John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet v Metavolcanic megabreccia within the tuff of Job Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tecx Megabreccia in tuff of Elevenmile Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet pa Blocks of propylitized andesite porphyry in tuff of Job Peak John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tjc Tuff of Job Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tlb Landslide breccia John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tpcu Upper cooling unit of tuff of Poco Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet JTRcl Upper limestone of the Clan Alpine sequence John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet s Argillite megabreccia within tuff of Elevenmile Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tgp Granite porphyry John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tpbr Tuff and breccia of Government Trail Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tdi Dacite intrusions John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Jq Middle and/or Lower Jurassic John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Kmd Dacitic volcanic-felsite flows and sedimentary breccia John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tfcgd Granodiorite porphyry John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tbi Basalt intrusions John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tfcgr Granite John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Trelc Rhyolite of East Lee Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tpsb Sandstone and breccia John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Qtc Talus, colluvium, and alluvium, undifferentiated John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tixl IXL pluton John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Td Diabase John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Qls Landslide deposits John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tolf Lava flows John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Jrmb Rhyolite megabreccia within tuff of Job Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tydat Dacite tuff John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet MZp Phyllite John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Todt Dacite tuff John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Qlbl Beach and shoreline deposits of Lake Lahontan John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Qay Young alluvial deposits John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tobr Breccia, conglomerate, and tuffs, undifferentiated John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Qes Eolian sand John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tddci Porphyritic dacite intrusions John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tec Tuff of Elevenmile Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Kmv Andesitic metavolcanic rocks John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tot Older tuffs, undifferentiated John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tha Hornblende andesite John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet TRca Argillite of the Clan Alpine sequence John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Qlf Sediments of Lake Dixie John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet ms Brecciated metashale and metasiltsone within the Tuff of Job Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tdg Diorite and granodiorite John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Qlb Beach and shoreline deposits of Lake Dixie John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Qbf Basin-fill deposits John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Trpm Rhyolite of Pirouette Mountain John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tya Andesite John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet TRcl Lower limestone of the Clan Alpine sequence John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tyr Younger rhyolite John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tap Andesite porphyry John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Kms Metasedimentary rocks, undifferentiated John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Qlfl Sediments of Lake Lahontan John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tydas Lacustrine sedimentary rocks John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tjcx Megabreccia within the tuff of Job Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tjp Tuff of Job Peak John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Kf Felsite John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tupc Tuff of upper part of Poco Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet a Megabreccia blocks of Andesite of Sheep Canyon within tuff of Elevenmile Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tasc Andesite of Sheep Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tsi Silicic intrusive rocks John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tbs Basaltic sedimentary rocks John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet q Quartzite megabreccia within the tuff of Job Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tsf Silicic lava flows John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Qaya Main-stream alluvium John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tb Basalt John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tddc Dacite of Diamond Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Qai Intermediate alluvial deposits John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tpcl Lower cooling unit of tuff of Poco Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tyda Younger dacite and andesite unit, undivided John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Ts Sedimentary rocks, undifferentiated John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet m Marble megabreccia within tuff of Elevenmile Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet QTa Very old alluvial deposits John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Qtf Tufa deposits John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Trp Rhyolite porphyry John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tts Tuffs and sedimentary rocks John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet TRs Siltstone and argillite of the Clan Alpine sequence John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tst Sedimentary tuff John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tr Rhyolite John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Klp La Plata Canyon pluton John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet IdentityConfidence Confidence that feature is correctly identified. GeMS certain Identity of a feature can be determined using relevant observations and scientific judgment; therefore, one can be reasonably confident in the credibility of this interpretation. Federal Geographic Data Committee [prepared for the Federal Geographic Data Committee by the U.S. Geological Survey], 2006, FGDC Digital Cartographic Standard for Geologic Map Symbolization: Reston, Va., Federal Geographic Data Committee Document Number FGDC-STD-013-2006, 290 p., 2 plates. questionable Identity of a feature cannot be determined using relevant observations and scientific judgment; therefore, one cannot be reasonably confident in the credibility of this interpretation. For example, IdentityConfidence = questionable is appropriate when a geologist reasons "I can see some kind of planar feature that separates map units in this outcrop, but I cannot be certain if it is a contact or a fault." Federal Geographic Data Committee [prepared for the Federal Geographic Data Committee by the U.S. Geological Survey], 2006, FGDC Digital Cartographic Standard for Geologic Map Symbolization: Reston, Va., Federal Geographic Data Committee Document Number FGDC-STD-013-2006, 290 p., 2 plates. Label Plain-text equivalent of the desired annotation for a feature: for example "14 Ma", or "^c" which (when used with the FGDC GeoAge font) results in the geologic map-unit label TRc (with TR run together to make the Triassic symbol). GeMS Unrepresentable domain Symbol Reference to a point marker, line symbol, or area-fill symbol that is used on the map graphic to denote the feature: perhaps a star for a K-Ar age locality, or a heavy black line for a fault. GeMS Unrepresentable domain DataSourceID Source of data; foreign key to table DataSources. GeMS ThisReport John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet This report Notes Additional information specific to a particular feature or table entry. GeMS Unrepresentable domain. Free text. Values of <null> or #null indicate no entry. MapUnitPolys_ID Primary key. GeMS Arbitrary string. Values should be unique within this database. DataSourcePolys Polygons that delineate data sources for all parts of the map. In the original file geodatabase, this dataset is found within the GeologicMap feature dataset. GeMS OBJECTID Internal feature number ESRI Unrepresentable domain Shape Internal geometry object ESRI Unrepresentable domain Shape_Length Internal feature length, double ESRI Unrepresentable domain Shape_Area Internal feature area, double ESRI Unrepresentable domain DataSourceID Source of data; foreign key to table DataSources. GeMS BellKatzer1987 Bell, J.W., and Katzer, T., 1987, Surficial geology, hydrology, and late Quaternary tectonics of the IXL Canyon area, Nevada: Nevada Bureau of Mines and Geology Bulletin 102, 52 p. This report JohnUnpub1994 D.A. John, unpublished mapping, 1994 This report John1992 John, D.A., 1992, Geologic map of the Table Mountain quadrangle, Churchill County, Nevada: U.S. Geological Survey Miscellaneous Field Studies Map MF–2194, scale 1:24,000. This report JohnSilberling1994 John, D.A., and Silberling, N.J., 1994, Geologic map of the La Plata Canyon quadrangle, Churchill County, Nevada: U.S. Geological Survey Geologic Quadrangle Map GQ-1710, scale 1:24,000, 8p. pamphlet. This report John1995 John, D.A., 1995b, Geologic map of the Pirouette Mountain quadrangle, Churchill County, Nevada: Nevada Bureau of Mines and Geology Field Studies Map 9, scale 1:24,000, 6 p. This report CalvinOthers2012 Calvin, W.M., Bell, J.W., and Hinx, N.H., 2012, Final technical report, Geothermal assessment of NAS Fallon land: Final technical report to Department of Navy, SEI Contract 10 TECHVAL #35014, University of Nevada, Reno, Great Basin Center for Geothermal Energy, 51 p., 1 plate, scale 1:48,000. This report JohnSilberlingUnpub1994 D.A. John and N.J. Silberling, unpublished mapping, 1994 This report John1993 John, D.A., 1993, Geologic map of the Job Peak quadrangle, Churchill County, Nevada: Nevada Bureau of Mines and Geology Field Studies Map 5, scale 1:24,000, 8 p. This report Notes Additional information specific to a particular feature or table entry. GeMS Unrepresentable domain. Free text. Values of <null> or #null indicate no entry. DataSourcePolys_ID Primary key. GeMS Arbitrary string. Values should be unique within this database. OverlayPolys Polygons that delineate underlying material, overlying material, or some aspect of earth materials other than the geologic map unit, e.g., dike swarm, alteration zone. On a map graphic, such polygons are commonly shown by a patterned overprint. In the original file geodatabase, this dataset is found within the GeologicMap feature dataset. GeMS OBJECTID Internal feature number ESRI Unrepresentable domain Shape Internal geometry object ESRI Unrepresentable domain Shape_Length Internal feature length, double ESRI Unrepresentable domain Shape_Area Internal feature area, double ESRI Unrepresentable domain Type Classifier that specifies what kind of geologic feature is represented by a database element: that a certain line within feature class ContactsAndFaults is a contact, or thrust fault, or water boundary; or that a point in GeochronPoints represents a K-Ar date. GeMS volcanic breccia A volcaniclastic rock composed of angular fragments greater than 2mm in size. Neuendorf, K.K.E., Mehl, J.P., Jr., and Jackson, J.A., eds., 2011, Glossary of Geology, Fifth Edition (revised): American Geosciences Institute, Alexandria, VA, 779 p. IdentityConfidence Confidence that feature is correctly identified. GeMS certain Identity of a feature can be determined using relevant observations and scientific judgment; therefore, one can be reasonably confident in the credibility of this interpretation. Federal Geographic Data Committee [prepared for the Federal Geographic Data Committee by the U.S. Geological Survey], 2006, FGDC Digital Cartographic Standard for Geologic Map Symbolization: Reston, Va., Federal Geographic Data Committee Document Number FGDC-STD-013-2006, 290 p., 2 plates. Label Plain-text equivalent of the desired annotation for a feature: for example "14 Ma", or "^c" which (when used with the FGDC GeoAge font) results in the geologic map-unit label TRc (with TR run together to make the Triassic symbol). GeMS Unrepresentable domain Symbol Reference to a point marker, line symbol, or area-fill symbol that is used on the map graphic to denote the feature: perhaps a star for a K-Ar age locality, or a heavy black line for a fault. GeMS Unrepresentable domain DataSourceID Source of data; foreign key to table DataSources. GeMS ThisReport John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet This report Notes Additional information specific to a particular feature or table entry. GeMS Unrepresentable domain. Free text. Values of <null> or #null indicate no entry. OverlayPolys_ID Primary key. GeMS Arbitrary string. Values should be unique within this database. ContactsAndFaults Contacts between map units, faults that bound map units, and associated dangling faults. Includes concealed faults and contacts, waterlines, snowfield and glacier boundaries, and map boundary. In the original file geodatabase, this dataset is found within the GeologicMap feature dataset. GeMS OBJECTID Internal feature number ESRI Unrepresentable domain Shape Internal geometry object ESRI Unrepresentable domain Shape_Length Internal feature length, double ESRI Unrepresentable domain Type Classifier that specifies what kind of geologic feature is represented by a database element: that a certain line within feature class ContactsAndFaults is a contact, or thrust fault, or water boundary; or that a point in GeochronPoints represents a K-Ar date. GeMS contact A plane or irregular surface between two types or ages of rock. Neuendorf, K.K.E., Mehl, J.P., Jr., and Jackson, J.A., eds., 2011, Glossary of Geology, Fifth Edition (revised): American Geosciences Institute, Alexandria, VA, 779 p. fault A discrete surface or zone of discrete surfaces separating two rock masses across which one mass has slid past the other. Neuendorf, K.K.E., Mehl, J.P., Jr., and Jackson, J.A., eds., 2011, Glossary of Geology, Fifth Edition (revised): American Geosciences Institute, Alexandria, VA, 779 p. normal fault A fault in which the hanging wall has moved downward relative to the footwall. The angle of the fault is usually 45-90 degrees, and in most cases close to 60 degrees. Neuendorf, K.K.E., Mehl, J.P., Jr., and Jackson, J.A., eds., 2011, Glossary of Geology, Fifth Edition (revised): American Geosciences Institute, Alexandria, VA, 779 p. low-angle normal fault A fault in which the hanging wall has moved downward relative to the footwall. The angle of the fault is less than 45 degrees. Neuendorf, K.K.E., Mehl, J.P., Jr., and Jackson, J.A., eds., 2011, Glossary of Geology, Fifth Edition (revised): American Geosciences Institute, Alexandria, VA, 779 p. thrust fault A fault with a dip of 45° or less over much of its extent, on which the hanging wall has moved upward relative to the footwall. Neuendorf, K.K.E., Mehl, J.P., Jr., and Jackson, J.A., eds., 2011, Glossary of Geology, Fifth Edition (revised): American Geosciences Institute, Alexandria, VA, 779 p. map boundary The boundary of the map. Unmapped areas within the boundary must be specifically labeled as such. John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet IsConcealed Flag for contacts and faults covered by overlying map unit. GeMS Unrepresentable domain LocationConfidenceMeters Estimated half-width in meters of positional uncertainty envelope; position is relative to other features in database. GeMS Positive real number. Value of -9, -99, or -999 indicates value is unknown. ExistenceConfidence Confidence that feature exists. GeMS certain Identity of a feature can be determined using relevant observations and scientific judgment; therefore, one can be reasonably confident in the credibility of this interpretation. Federal Geographic Data Committee [prepared for the Federal Geographic Data Committee by the U.S. Geological Survey], 2006, FGDC Digital Cartographic Standard for Geologic Map Symbolization: Reston, Va., Federal Geographic Data Committee Document Number FGDC-STD-013-2006, 290 p., 2 plates. questionable Identity of a feature cannot be determined using relevant observations and scientific judgment; therefore, one cannot be reasonably confident in the credibility of this interpretation. For example, IdentityConfidence = questionable is appropriate when a geologist reasons "I can see some kind of planar feature that separates map units in this outcrop, but I cannot be certain if it is a contact or a fault." Federal Geographic Data Committee [prepared for the Federal Geographic Data Committee by the U.S. Geological Survey], 2006, FGDC Digital Cartographic Standard for Geologic Map Symbolization: Reston, Va., Federal Geographic Data Committee Document Number FGDC-STD-013-2006, 290 p., 2 plates. IdentityConfidence Confidence that feature is correctly identified. GeMS certain Identity of a feature can be determined using relevant observations and scientific judgment; therefore, one can be reasonably confident in the credibility of this interpretation. Federal Geographic Data Committee [prepared for the Federal Geographic Data Committee by the U.S. Geological Survey], 2006, FGDC Digital Cartographic Standard for Geologic Map Symbolization: Reston, Va., Federal Geographic Data Committee Document Number FGDC-STD-013-2006, 290 p., 2 plates. questionable Identity of a feature cannot be determined using relevant observations and scientific judgment; therefore, one cannot be reasonably confident in the credibility of this interpretation. For example, IdentityConfidence = questionable is appropriate when a geologist reasons "I can see some kind of planar feature that separates map units in this outcrop, but I cannot be certain if it is a contact or a fault." Federal Geographic Data Committee [prepared for the Federal Geographic Data Committee by the U.S. Geological Survey], 2006, FGDC Digital Cartographic Standard for Geologic Map Symbolization: Reston, Va., Federal Geographic Data Committee Document Number FGDC-STD-013-2006, 290 p., 2 plates. Label Plain-text equivalent of the desired annotation for a feature: for example "14 Ma", or "^c" which (when used with the FGDC GeoAge font) results in the geologic map-unit label TRc (with TR run together to make the Triassic symbol). GeMS Unrepresentable domain Symbol Reference to a point marker, line symbol, or area-fill symbol that is used on the map graphic to denote the feature: perhaps a star for a K-Ar age locality, or a heavy black line for a fault. GeMS Unrepresentable domain DataSourceID Source of data; foreign key to table DataSources. GeMS ThisReport John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet This report Notes Additional information specific to a particular feature or table entry. GeMS Unrepresentable domain. Free text. Values of <null> or #null indicate no entry. ContactsAndFaults_ID Primary key. GeMS Arbitrary string. Values should be unique within this database. MapUnitLines Lines that record distribution of map units of narrow, linear extent on the particular map horizon. In the original file geodatabase, this dataset is found within the GeologicMap feature dataset. GeMS OBJECTID Internal feature number ESRI Unrepresentable domain Shape Internal geometry object ESRI Unrepresentable domain Shape_Length Internal feature length, double ESRI Unrepresentable domain MapUnit Short plain-text identifier of the map unit. Foreign key to DescriptionOfMapUnits table. GeMS Td Diabase John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tor Older rhyolite John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tsi Silicic intrusive rocks John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tgp Granite porphyry John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tydai Dacite and andesite intrusions John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tyr Younger rhyolite John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tfcgr Granite John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tsd Silicic dikes John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Trpm Rhyolite of Pirouette Mountain John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet IsConcealed Flag for contacts and faults covered by overlying map unit. GeMS Unrepresentable domain LocationConfidenceMeters Estimated half-width in meters of positional uncertainty envelope; position is relative to other features in database. GeMS Positive real number. Value of -9, -99, or -999 indicates value is unknown. ExistenceConfidence Confidence that feature exists. GeMS certain Identity of a feature can be determined using relevant observations and scientific judgment; therefore, one can be reasonably confident in the credibility of this interpretation. Federal Geographic Data Committee [prepared for the Federal Geographic Data Committee by the U.S. Geological Survey], 2006, FGDC Digital Cartographic Standard for Geologic Map Symbolization: Reston, Va., Federal Geographic Data Committee Document Number FGDC-STD-013-2006, 290 p., 2 plates. IdentityConfidence Confidence that feature is correctly identified. GeMS certain Identity of a feature can be determined using relevant observations and scientific judgment; therefore, one can be reasonably confident in the credibility of this interpretation. Federal Geographic Data Committee [prepared for the Federal Geographic Data Committee by the U.S. Geological Survey], 2006, FGDC Digital Cartographic Standard for Geologic Map Symbolization: Reston, Va., Federal Geographic Data Committee Document Number FGDC-STD-013-2006, 290 p., 2 plates. Label Plain-text equivalent of the desired annotation for a feature: for example "14 Ma", or "^c" which (when used with the FGDC GeoAge font) results in the geologic map-unit label TRc (with TR run together to make the Triassic symbol). GeMS Unrepresentable domain Symbol Reference to a point marker, line symbol, or area-fill symbol that is used on the map graphic to denote the feature: perhaps a star for a K-Ar age locality, or a heavy black line for a fault. GeMS Unrepresentable domain PlotAtScale At what scale (or larger) should this observation or analysis be plotted? At smaller scales, it should not be plotted. Useful to prevent crowding of display at small scales and to display progressively more data at larger and larger scales. Value is scale denominator. GeMS Positive real number. DataSourceID Source of data; foreign key to table DataSources. GeMS ThisReport John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet This report Notes Additional information specific to a particular feature or table entry. GeMS Unrepresentable domain. Free text. Values of <null> or #null indicate no entry. MapUnitLines_ID Primary key. GeMS Arbitrary string. Values should be unique within this database. OrientationPoints Point structure data (e.g., bedding attitudes, foliation attitudes, slip vectors measured at a point, etc.), one point per measurement. Multiple measurements at a single station (e.g., bedding and cleavage) should have the same StationsID. In the original file geodatabase, this dataset is found within the GeologicMap feature dataset. GeMS OBJECTID Internal feature number ESRI Unrepresentable domain Shape Internal geometry object ESRI Unrepresentable domain Type Classifier that specifies what kind of geologic feature is represented by a database element: that a certain line within feature class ContactsAndFaults is a contact, or thrust fault, or water boundary; or that a point in GeochronPoints represents a K-Ar date. GeMS vertical bedding, showing strike A relatively conformable succession of genetically related laminae or lamina-sets bounded by surfaces (called bedding surfaces) of erosion, non-deposition or their correlative conformities. Orientation defined by strike where bedding dips 90 degrees and original stratigraphic top is unspecified or unknown. Neuendorf, K.K.E., Mehl, J.P., Jr., and Jackson, J.A., eds., 2011, Glossary of Geology, Fifth Edition (revised): American Geosciences Institute, Alexandria, VA, 779 p. horizontal bedding A relatively conformable succession of genetically related laminae or lamina-sets bounded by surfaces (called bedding surfaces) of erosion, non-deposition or their correlative conformities. Orientation is subhorizontal and original stratigraphic top is up. Neuendorf, K.K.E., Mehl, J.P., Jr., and Jackson, J.A., eds., 2011, Glossary of Geology, Fifth Edition (revised): American Geosciences Institute, Alexandria, VA, 779 p. inclined bedding, showing strike and dip A relatively conformable succession of genetically related laminae or lamina-sets bounded by surfaces (called bedding surfaces) of erosion, non-deposition or their correlative conformities. Orientation defined by strike and dip where original stratigraphic top is upright. Neuendorf, K.K.E., Mehl, J.P., Jr., and Jackson, J.A., eds., 2011, Glossary of Geology, Fifth Edition (revised): American Geosciences Institute, Alexandria, VA, 779 p. vertical eutaxitic foliation, showing strike Pumice fragments in a welded pyroclastic rock which have been compacted into parallel, disc-shaped lenses; also called "fiamme." Orientation defined by strike where fabric dips 90 degrees. Neuendorf, K.K.E., Mehl, J.P., Jr., and Jackson, J.A., eds., 2011, Glossary of Geology, Fifth Edition (revised): American Geosciences Institute, Alexandria, VA, 779 p. inclined flow foliation, showing strike and dip The structure of an igneous rock, characterized by alternating layers of color, mineralogic composition, and/or texture, formed as a result of the flow of magma or lava. Orientation defined by strike and dip. Neuendorf, K.K.E., Mehl, J.P., Jr., and Jackson, J.A., eds., 2011, Glossary of Geology, Fifth Edition (revised): American Geosciences Institute, Alexandria, VA, 779 p. overturned bedding, showing strike and dip A relatively conformable succession of genetically related laminae or lamina-sets bounded by surfaces (called bedding surfaces) of erosion, non-deposition or their correlative conformities. Orientation defined by strike and dip where original stratigraphic top points down. Neuendorf, K.K.E., Mehl, J.P., Jr., and Jackson, J.A., eds., 2011, Glossary of Geology, Fifth Edition (revised): American Geosciences Institute, Alexandria, VA, 779 p. inclined metamorphic or tectonic foliation, showing strike and dip Planar parallelism of flaky minerals and compositional layering. Orientation defined by strike and dip. Neuendorf, K.K.E., Mehl, J.P., Jr., and Jackson, J.A., eds., 2011, Glossary of Geology, Fifth Edition (revised): American Geosciences Institute, Alexandria, VA, 779 p. inclined eutaxitic foliation, showing strike and dip Pumice fragments in a welded pyroclastic rock which have been compacted into parallel, disc-shaped lenses; also called "fiamme." Orientation defined by strike and dip. Neuendorf, K.K.E., Mehl, J.P., Jr., and Jackson, J.A., eds., 2011, Glossary of Geology, Fifth Edition (revised): American Geosciences Institute, Alexandria, VA, 779 p. vertical flow foliation, showing strike The structure of an igneous rock, characterized by alternating layers of color, mineralogic composition, and/or texture, formed as a result of the flow of magma or lava. Orientation defined by strike where fabric dips 90 degrees. Neuendorf, K.K.E., Mehl, J.P., Jr., and Jackson, J.A., eds., 2011, Glossary of Geology, Fifth Edition (revised): American Geosciences Institute, Alexandria, VA, 779 p. vertical metamorphic or tectonic foliation, showing strike Planar parallelism of flaky minerals and compositional layering. Orientation defined by strike where fabric dips 90 degrees. Neuendorf, K.K.E., Mehl, J.P., Jr., and Jackson, J.A., eds., 2011, Glossary of Geology, Fifth Edition (revised): American Geosciences Institute, Alexandria, VA, 779 p. Azimuth Strike or trend, measured in degrees clockwise from geographic North. Use right-hand rule (dip is to right of azimuth direction). Horizontal planar features may have any azimuth. GeMS 0 360 degrees (angular measure) Inclination Dip or plunge, measured in degrees down from horizontal. Negative values allowed when specifying vectors (not axes) that point above the horizon, e.g., paleocurrents. Types defined as horizontal (e.g., horizontal bedding) shall have Inclination=0. GeMS -90 90 degrees (angular measure) Symbol Reference to a point marker, line symbol, or area-fill symbol that is used on the map graphic to denote the feature: perhaps a star for a K-Ar age locality, or a heavy black line for a fault. GeMS Unrepresentable domain Label Plain-text equivalent of the desired annotation for a feature: for example "14 Ma", or "^c" which (when used with the FGDC GeoAge font) results in the geologic map-unit label TRc (with TR run together to make the Triassic symbol). GeMS Unrepresentable domain LocationConfidenceMeters Estimated half-width in meters of positional uncertainty envelope; position is relative to other features in database. GeMS Positive real number. Value of -9, -99, or -999 indicates value is unknown. IdentityConfidence Confidence that feature is correctly identified. GeMS certain Identity of a feature can be determined using relevant observations and scientific judgment; therefore, one can be reasonably confident in the credibility of this interpretation. Federal Geographic Data Committee [prepared for the Federal Geographic Data Committee by the U.S. Geological Survey], 2006, FGDC Digital Cartographic Standard for Geologic Map Symbolization: Reston, Va., Federal Geographic Data Committee Document Number FGDC-STD-013-2006, 290 p., 2 plates. OrientationConfidenceDegrees Estimated angular precision of combined azimuth AND inclination measurements, in degrees. GeMS Positive real number. Value of -9, -99, or -999 indicates value is unknown. PlotAtScale At what scale (or larger) should this observation or analysis be plotted? At smaller scales, it should not be plotted. Useful to prevent crowding of display at small scales and to display progressively more data at larger and larger scales. Value is scale denominator. GeMS Positive real number. StationsID Foreign key to Stations point feature class. GeMS Unrepresentable domain MapUnit Short plain-text identifier of the map unit. Foreign key to DescriptionOfMapUnits table. GeMS Tydas Lacustrine sedimentary rocks John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Qay Young alluvial deposits John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tobr Breccia, conglomerate, and tuffs, undifferentiated John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet TRcs Calcareous siltstone and sandstone of the Clan Alpine sequence John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tjcx Megabreccia within the tuff of Job Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tjp Tuff of Job Peak John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tfcgr Granite John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Kf Felsite John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Trelc Rhyolite of East Lee Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tsd Silicic dikes John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tupc Tuff of upper part of Poco Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tpsb Sandstone and breccia John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tec Tuff of Elevenmile Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Kmv Andesitic metavolcanic rocks John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tot Older tuffs, undifferentiated John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tsi Silicic intrusive rocks John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tsf Silicic lava flows John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet TRca Argillite of the Clan Alpine sequence John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tb Basalt John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tddc Dacite of Diamond Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tpcl Lower cooling unit of tuff of Poco Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tecx Megabreccia in tuff of Elevenmile Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tyda Younger dacite and andesite unit, undivided John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tjc Tuff of Job Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tolf Lava flows John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Ts Sedimentary rocks, undifferentiated John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tpcu Upper cooling unit of tuff of Poco Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tts Tuffs and sedimentary rocks John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Trpm Rhyolite of Pirouette Mountain John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tydat Dacite tuff John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet JTRcl Upper limestone of the Clan Alpine sequence John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet TRs Siltstone and argillite of the Clan Alpine sequence John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tya Andesite John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet TRcl Lower limestone of the Clan Alpine sequence John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tpbr Tuff and breccia of Government Trail Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tdi Dacite intrusions John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tyr Younger rhyolite John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet MZp Phyllite John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Todt Dacite tuff John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tst Sedimentary tuff John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Kmd Dacitic volcanic-felsite flows and sedimentary breccia John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Kms Metasedimentary rocks, undifferentiated John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet LocationSourceID Source of location; foreign key to table DataSources. GeMS John1992 John, D.A., 1992, Geologic map of the Table Mountain quadrangle, Churchill County, Nevada: U.S. Geological Survey Miscellaneous Field Studies Map MF–2194, scale 1:24,000. This report JohnSilberling1994 John, D.A., and Silberling, N.J., 1994, Geologic map of the La Plata Canyon quadrangle, Churchill County, Nevada: U.S. Geological Survey Geologic Quadrangle Map GQ-1710, scale 1:24,000, 8p. pamphlet. This report John1995 John, D.A., 1995b, Geologic map of the Pirouette Mountain quadrangle, Churchill County, Nevada: Nevada Bureau of Mines and Geology Field Studies Map 9, scale 1:24,000, 6 p. This report ThisReport John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet This report JohnSilberlingUnpub1994 D.A. John and N.J. Silberling, unpublished mapping, 1994 This report John1993 John, D.A., 1993, Geologic map of the Job Peak quadrangle, Churchill County, Nevada: Nevada Bureau of Mines and Geology Field Studies Map 5, scale 1:24,000, 8 p. This report OrientationSourceID Source of orientation data; foreign key to table DataSources. GeMS John1992 John, D.A., 1992, Geologic map of the Table Mountain quadrangle, Churchill County, Nevada: U.S. Geological Survey Miscellaneous Field Studies Map MF–2194, scale 1:24,000. This report JohnSilberling1994 John, D.A., and Silberling, N.J., 1994, Geologic map of the La Plata Canyon quadrangle, Churchill County, Nevada: U.S. Geological Survey Geologic Quadrangle Map GQ-1710, scale 1:24,000, 8p. pamphlet. This report John1995 John, D.A., 1995b, Geologic map of the Pirouette Mountain quadrangle, Churchill County, Nevada: Nevada Bureau of Mines and Geology Field Studies Map 9, scale 1:24,000, 6 p. This report ThisReport John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet This report JohnSilberlingUnpub1994 D.A. John and N.J. Silberling, unpublished mapping, 1994 This report John1993 John, D.A., 1993, Geologic map of the Job Peak quadrangle, Churchill County, Nevada: Nevada Bureau of Mines and Geology Field Studies Map 5, scale 1:24,000, 8 p. This report Notes Additional information specific to a particular feature or table entry. GeMS Unrepresentable domain. Free text. Values of <null> or #null indicate no entry. OrientationPoints_ID Primary key. GeMS Arbitrary string. Values should be unique within this database. GeochronPoints Point locations of samples and accompanying geochronological measurements. Type field identifies geochronological method. In the original file geodatabase, this dataset is found within the GeologicMap feature dataset. GeMS OBJECTID Internal feature number ESRI Unrepresentable domain Shape Internal geometry object ESRI Unrepresentable domain Type Classifier that specifies what kind of geologic feature is represented by a database element: that a certain line within feature class ContactsAndFaults is a contact, or thrust fault, or water boundary; or that a point in GeochronPoints represents a K-Ar date. GeMS K-Ar Determination of the age of a mineral or rock in years, based on measurement of the ratio of radiogenic argon-40 to potassium-40 and the known radioactive decay rate of potassium to argon-40. Neuendorf, K.K.E., Mehl, J.P., Jr., and Jackson, J.A., eds., 2011, Glossary of Geology, Fifth Edition (revised): American Geosciences Institute, Alexandria, VA, 779 p. Ar-Ar Determination of an age for a mineral or rock in years based on the ratio of radiogenic argon-40 to potassium-40. The sample to be dated is first irradiated with neutrons, converting some potassium-39 to argon-39. Argon is then extracted from the sample (either in one step or incrementally), and its isotopic composition analyzed. The amount of argon-39 is a measure of potassium content, and the ratio of radiogenic argon-40 to argon-39 is a function of age. Neuendorf, K.K.E., Mehl, J.P., Jr., and Jackson, J.A., eds., 2011, Glossary of Geology, Fifth Edition (revised): American Geosciences Institute, Alexandria, VA, 779 p. U-Pb Determination of an age for a mineral or rock in years based on the known radioactive decay rate of uranium-238 to lead-206 and uranium-235 to lead-207. The determined lead-207/lead-206 ratio can be used to compute a useful but not independent lead-lead age. Whether all possible dates are concordant or discordant is useful for evaluating the results of this method, used alone or in comparison with other methods, and in determining whether the initially closed system has been disturbed. Neuendorf, K.K.E., Mehl, J.P., Jr., and Jackson, J.A., eds., 2011, Glossary of Geology, Fifth Edition (revised): American Geosciences Institute, Alexandria, VA, 779 p. FieldSampleID Sample ID given at time of collection. GeMS Unrepresentable domain AlternateSampleID Museum #, lab #, etc. GeMS Unrepresentable domain MapUnit Short plain-text identifier of the map unit. Foreign key to DescriptionOfMapUnits table. GeMS Tfcgd Granodiorite porphyry John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tobr Breccia, conglomerate, and tuffs, undifferentiated John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tjp Tuff of Job Peak John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tbi Basalt intrusions John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tfcgr Granite John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Kf Felsite John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tsd Silicic dikes John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tupc Tuff of upper part of Poco Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tasc Andesite of Sheep Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tec Tuff of Elevenmile Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Kmv Andesitic metavolcanic rocks John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tot Older tuffs, undifferentiated John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tsi Silicic intrusive rocks John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tha Hornblende andesite John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tixl IXL pluton John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tb Basalt John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tddc Dacite of Diamond Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tpcl Lower cooling unit of tuff of Poco Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tyda Younger dacite and andesite unit, undivided John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tjc Tuff of Job Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tolf Lava flows John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Ts Sedimentary rocks, undifferentiated John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Jrmb Rhyolite megabreccia within tuff of Job Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Alteration Hydrothermal alteration minerals John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Trp Rhyolite porphyry John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tpcu Upper cooling unit of tuff of Poco Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Trpm Rhyolite of Pirouette Mountain John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tgp Granite porphyry John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tpbr Tuff and breccia of Government Trail Canyon John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tyr Younger rhyolite John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Todt Dacite tuff John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tst Sedimentary tuff John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Tap Andesite porphyry John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Klp La Plata Canyon pluton John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Symbol Reference to a point marker, line symbol, or area-fill symbol that is used on the map graphic to denote the feature: perhaps a star for a K-Ar age locality, or a heavy black line for a fault. GeMS Unrepresentable domain Label Plain-text equivalent of the desired annotation for a feature: for example "14 Ma", or "^c" which (when used with the FGDC GeoAge font) results in the geologic map-unit label TRc (with TR run together to make the Triassic symbol). GeMS Unrepresentable domain LocationConfidenceMeters Estimated half-width in meters of positional uncertainty envelope; position is relative to other features in database. GeMS Positive real number. Value of -9, -99, or -999 indicates value is unknown. PlotAtScale At what scale (or larger) should this observation or analysis be plotted? At smaller scales, it should not be plotted. Useful to prevent crowding of display at small scales and to display progressively more data at larger and larger scales. Value is scale denominator. GeMS Positive real number. MaterialAnalyzed Earth-material which was analyzed, e.g., wood, shell, zircon, basalt, whole-rock. GeMS Unrepresentable domain NumericAge Age of map unit as shown in Description of Map Units. Examples of values are "late Holocene", "Pliocene and Miocene", "Lower Cretaceous". GeMS Unrepresentable domain AgePlusError Positive (older) age error, measured in AgeUnits. Type of error (RMSE, 1 sigma, 2 sigma, 95% confidence limit) should be stated in Notes field. GeMS Positive real number. Value of -9, -99, or -999 indicates value is unknown. AgeMinusError Negative (younger) age error, measured in AgeUnits. Type of error (RMSE, 1 sigma, 2 sigma, 95% confidence limit) should be stated in Notes field. GeMS Positive real number. Value of -9, -99, or -999 indicates value is unknown. ErrorMeasure Measure of error whose values are recorded in AgePlusError and AgeMinusError fields GeMS Unrepresentable domain AgeUnits Units for NumericAge, AgePlusError, AgeMinusError. GeMS Ma Mega-annum, where annum is age in years before present, with "present" fixed as 1950. It is not equivalent to the elapsed time interval or duration in "millions of years" (myr). Neuendorf, K.K.E., Mehl, J.P., Jr., and Jackson, J.A., eds., 2011, Glossary of Geology, Fifth Edition (revised): American Geosciences Institute, Alexandria, VA, 779 p. StationsID Foreign key to Stations point feature class. GeMS Unrepresentable domain LocationSourceID Source of location; foreign key to table DataSources. GeMS HenryJohn2013 Henry, C.D., and John, D.A., 2013, Magmatism, ash-flow tuffs, and calderas of the Ignimbrite Flareup in the Western Nevada Volcanic Field, Great Basin, USA: Geosphere, v. 9, no. 4, p. 951–1008. This report HudsonOthers2000 Hudson, M.R., John, D.A., Conrad, J.E., and McKee, E.H., 2000, Style and age of late Oligocene-early Miocene deformation in the southern Stillwater Range, west central Nevada: Paleomagnetism, geochronology, and field relations: Journal of Geophysical Research—Solid Earth, v. 105, no. 1, p. 929–954. This report ColganOthers2017 Colgan, J.P., John, D.A., Henry, C.D., and Watts, K.E., 2017, Geochemical and geochronologic data from the Stillwater Range, Clan Alpine, and Desatoya Mountains, Nevada (ver. 3.0, December 2023): U.S. Geological Survey data release, https://doi.org/10.5066/F7P26X2V. This report ColganOthers2018 Colgan, J.P., John, D.A., Henry, C.D., and Watts, K.E., 2018, Insights into the emplacement of upper-crustal plutons and their relationship to large silicic calderas, from field relationships, geochronology, and zircon trace element geochemistry in the Stillwater – Clan Alpine caldera complex, western Nevada, USA: Journal of Volcanology and Geothermal Research, v. 349, p. 163–176. This report StewartOthers1994 Stewart, J.H., McKee, E.H., and John, D.A., 1994, Map showing compilation of isotopic ages of Cenozoic rocks in the Reno 1° × 2° quadrangle, Nevada and California: U.S. Geological Survey Miscellaneous Field Studies Map MF-2154-D, scale 1:250,000, 19 p. pamphlet. This report AnalysisSourceID Source of analysis; foreign key to table DataSources. GeMS HenryJohn2013 Henry, C.D., and John, D.A., 2013, Magmatism, ash-flow tuffs, and calderas of the Ignimbrite Flareup in the Western Nevada Volcanic Field, Great Basin, USA: Geosphere, v. 9, no. 4, p. 951–1008. This report HudsonOthers2000 Hudson, M.R., John, D.A., Conrad, J.E., and McKee, E.H., 2000, Style and age of late Oligocene-early Miocene deformation in the southern Stillwater Range, west central Nevada: Paleomagnetism, geochronology, and field relations: Journal of Geophysical Research—Solid Earth, v. 105, no. 1, p. 929–954. This report ColganOthers2017 Colgan, J.P., John, D.A., Henry, C.D., and Watts, K.E., 2017, Geochemical and geochronologic data from the Stillwater Range, Clan Alpine, and Desatoya Mountains, Nevada (ver. 3.0, December 2023): U.S. Geological Survey data release, https://doi.org/10.5066/F7P26X2V. This report ColganOthers2018 Colgan, J.P., John, D.A., Henry, C.D., and Watts, K.E., 2018, Insights into the emplacement of upper-crustal plutons and their relationship to large silicic calderas, from field relationships, geochronology, and zircon trace element geochemistry in the Stillwater – Clan Alpine caldera complex, western Nevada, USA: Journal of Volcanology and Geothermal Research, v. 349, p. 163–176. This report StewartOthers1994 Stewart, J.H., McKee, E.H., and John, D.A., 1994, Map showing compilation of isotopic ages of Cenozoic rocks in the Reno 1° × 2° quadrangle, Nevada and California: U.S. Geological Survey Miscellaneous Field Studies Map MF-2154-D, scale 1:250,000, 19 p. pamphlet. This report Notes Additional information specific to a particular feature or table entry. GeMS Unrepresentable domain. Free text. Values of <null> or #null indicate no entry. GeochronPoints_ID Primary key. GeMS Arbitrary string. Values should be unique within this database. FossilPoints Point locations where fossils have been collected and described GeMS OBJECTID Internal feature number ESRI Unrepresentable domain Shape Internal geometry object ESRI Unrepresentable domain Type Classifier that specifies what kind of geologic feature is represented by a database element: that a certain line within feature class ContactsAndFaults is a contact, or thrust fault, or water boundary; or that a point in GeochronPoints represents a K-Ar date. GeMS fossil locality Location where fossils were collected for paleontologic age determination John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet StationsID Foreign key to Stations point feature class. GeMS Unrepresentable domain MapUnit Short plain-text identifier of the map unit. Foreign key to DescriptionOfMapUnits table. GeMS TRcl Lower limestone of the Clan Alpine sequence John, D.A., Colgan, J.P., Berry, M.E., Henry, C.D., and Silberling, N.J., 2024, Geologic map of the southern Stillwater Range, Nevada: U.S. Geological Survey Scientific Investigations Map 3521, 2 sheets, scale 1:24,000, 39-p. pamphlet Label Plain-text equivalent of the desired annotation for a feature: for example "14 Ma", or "^c" which (when used with the FGDC GeoAge font) results in the geologic map-unit label TRc (with TR run together to make the Triassic symbol). GeMS Unrepresentable domain Symbol Reference to a point marker, line symbol, or area-fill symbol that is used on the map graphic to denote the feature: perhaps a star for a K-Ar age locality, or a heavy black line for a fault. GeMS Unrepresentable domain FieldSampleID Sample ID given at time of collection. GeMS Unrepresentable domain AlternateSampleID Museum #, lab #, etc. GeMS Unrepresentable domain MaterialAnalyzed Earth-material which was analyzed, e.g., wood, shell, zircon, basalt, whole-rock. GeMS Unrepresentable domain PlotAtScale At what scale (or larger) should this observation or analysis be plotted? At smaller scales, it should not be plotted. Useful to prevent crowding of display at small scales and to display progressively more data at larger and larger scales. Value is scale denominator. GeMS Positive real number. LocationConfidenceMeters Estimated half-width in meters of positional uncertainty envelope; position is relative to other features in database. GeMS Positive real number. Value of -9, -99, or -999 indicates value is unknown. FossilForms Description of fossil or fossil assemblage found at locality GeMS Unrepresentable domain FossilAge Age of map unit as shown in Description of Map Units. Examples of values are "late Holocene", "Pliocene and Miocene", "Lower Cretaceous". GeMS Unrepresentable domain LocationSourceID Source of location; foreign key to table DataSources. GeMS JohnSilberling1994 John, D.A., and Silberling, N.J., 1994, Geologic map of the La Plata Canyon quadrangle, Churchill County, Nevada: U.S. Geological Survey Geologic Quadrangle Map GQ-1710, scale 1:24,000, 8p. pamphlet. This report FossilFormsSourceID Identifies source of fossil data for this point feature. Foreign key to Identifies source of fossil data for this point feature. Foreign key to DataSources table GeMS Unrepresentable domain FossilAgeSourceID Identifies source of age interpretation for this fossil. Foreign key to DataSources table GeMS Unrepresentable domain Notes Additional information specific to a particular feature or table entry. GeMS Unrepresentable domain. Free text. Values of <null> or #null indicate no entry. FossilPoints_ID Primary key. GeMS Arbitrary string. Values should be unique within this database. Joseph P. Colgan mailing and physical

Building 25

Lakewood CO 80401 303-236-1021 Any use of trade, product or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Geological Survey. Although this information product, for the most part, is in the public domain, it also contains copyrighted materials as noted in the text. Permission to reproduce copyrighted items for other than personal use must be secured from the copyright owner. This database has been approved for release and publication by the Director of the USGS. Although this database has been subjected to rigorous review and is substantially complete, the USGS reserves the right to revise the data pursuant to further analysis and review. Furthermore, it is released on condition that neither the USGS nor the United States Government may be held liable for any damages resulting from its authorized or unauthorized use. Although these data have been processed successfully on a computer system at the U.S. Geological Survey, no warranty expressed or implied is made regarding the display or utility of the data on any other system, or for general or scientific purposes, nor shall the act of distribution constitute any such warranty. The U.S. Geological Survey shall not be held liable for improper or incorrect use of the data described and/or contained herein. Digital Data https://doi.org/10.5066/P9WW1EUF. None 20241101 Joseph P. Colgan U.S. Geological Survey mailing and physical

Building 25

Lakewood CO 80225 303-236-1021 FGDC Content Standard for Digital Geospatial Metadata FGDC-STD-001-1998