Andrew J. Cyr David M. Miller 20230404 1.0 vector digital data https://doi.org/10.5066/P9WTKPBP Andrew J. Cyr David M. Miller 2023 publication n/a US Geological Survey https://doi.org/10.3133/ofr20231014 This preliminary geologic map presents mapping of the Leuhman Ridge area of Edwards Air Force Base, California, conducted between April 2020 and June 2021. The report focuses on surficial materials and bedrock to evaluate potential faults and other geologic features that may influence groundwater movement. The preliminary work confirms that the Spring Fault, previously mapped by Dibblee (1960, 1967), is a Quaternary-active fault but does not find convincing evidence to support the existence of the Leuhman Fault (Dibblee, 1960; 1967) within the map area. Several more possible and probable faults are identified by a combination of geomorphic lineaments and brecciated rock. Pleistocene and Holocene eolian deposits are widespread, manifesting as sand sheets, dunes, and admixtures into alluvial fans. Also, an incised pediment forms much of the upland south of Leuhman Ridge. In general, field observations indicate that Quaternary alluvial and eolian deposits are thin; this suggests that secondary bedrock porosity and permeability, defined by degree of weathering and fracture density that includes fault-related fracturing, are more important factors in the location and flow patterns of groundwater. This digital map database represents the general distribution of surficial geologic units and related landforms and structures in the area around Leuhman Ridge, in the Air Force Research Lab at Edwards Air Force Base, southern California. The database delineates map units that are identified by general age and lithology following the stratigraphic nomenclature of previous surficial geologic mapping in the Mojave Desert by the U.S. Geological Survey (USGS). The present map was created with the support of the USGS California Water Science Center, Air Force Civil Engineer Center, and the Air Force Research Laboratory at Edwards Air Force Base to provide an updated depiction of the geologic framework for the purpose of better understanding possible groundwater flow pathways. This metadata report provides an overview of the data content of this GeMS geodatabase and associated files. The Supplemental Information section of this metadata report contains additional information about the structure and content of the geodatabase and associated files. Detailed attribute, process step, and data quality information is provided in the metadata reports for each feature class and non-spatial table. Refer to the accompanying map and pamphlet for cartographic, descriptive, and interpretive presentations of the information. ofr20231014.gdb is a composite geodataset that conforms to "GeMS (Geologic Map Schema)--a standard format for digital publication of geologic maps, version 2.8.1, 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. The metadata records that are included with the OPEN file package are largely duplicated from the metadata for the geodatabase, and have not been modified to reflect schema and content changes that resulted during the conversion process (such as changes to field names). The metadata therefore, does not accurately describe all aspects of the shapefiles, and the user is advised to consult the GeMS documentation and the documentation for the GeMS "Translate to Shapefiles" tool available at https://github.com/usgs/gems-tools-arcmap/wiki/GeMS_ToolsDocumentation#TranslateToShapefiles for more information. 20230421 publication date Complete None planned -117.74914 -117.61382 34.99433 34.89981 ISO 19115 Topic Category geoscientificInformation USGS Thesaurus maps and atlases surficial geological units geologic maps sedimentation unconsolidated deposits faulting (geologic) geologic contacts geomorphology geologic processes tectonic processes geochronology luminescence dating groundwater USGS Metadata Identifier USGS:61e85876d34e8b818ad894c7 Common geographic areas California Mojave Kern San Bernardino Kramer Hills Boron Red Buttes Edwards Air Force Base Leuhman Ridge None. Please see 'Distribution Info' for details. Not for use at scales larger than 1:18,000. Any derivative products utilizing these datasets shall clearly indicate their source. If users modify the data in any way they are obligated to describe the types of modifications they have performed. User specifically agrees not to misrepresent these datasets, nor to imply that changes they made were approved by the USGS. Andrew Cyr U.S. Geological Survey Research Geologist mailing

PO Box 158

Moffett Field CA 94035 USA 650-439-2820 acyr@usgs.gov This digital database was prepared by Andrew Cyr and David Miller (both USGS). The GeMS toolbox (https://github.com/usgs/gems-tools-arcmap) and GeMS database workflows developed by Tracey Felger (USGS) were invaluable in creating, working with, and validating the geodatabase. Metadata was prepared using the USGS Metadata Wizard (https://www.usgs.gov/software/metadatawizard). Scientific reviews were provided by Scott Bennett and Ben Melosh (both USGS). Digital review was provided by Tracey Felger and Chad Kwiatkowski (both USGS at the time of review). Editorial review of the accompanying pamphlet and map sheet was provided by Regan Austin (USGS). Funding support for this work came from the USGS California Water Science Center and the Air Force Civil Engineer Center and Air Force Research Laboratory, Edwards Air Force Base, California, and from the National Cooperative Geologic Mapping Program to the Western Basin and Range - Eastern California Shear Zone geologic mapping project in the USGS Geology, Minerals, Energy, and Geophysics Science Center (GMEGSC). This database and associated files were created and organized in ESRI's ArcGIS Desktop and ArcGIS Pro software packages. Some tables were organized in Microsoft Office365 Excel prior to being imported and incorporated into the GIS data. Metadata was prepared using the USGS Metadata Wizard versions. 2.0.6 and 2.0.7. Shannon A. Mahan Harrison J. Gray Andrew J. Cyr Emma T. Krolczyk David M. Miller 2021 dataset https://ngmdb.usgs.gov U.S. Geological Survey https://doi.org/10.5066/p9ixg2jx Andrew J. Cyr David M. Miller 20230421 publication Open-File Report 2023-1014 https://pubs.er.usgs.gov/ U.S. Geological Survey Attribute integrity was evaluated using scripted and visual workflows. Scripted workflows included using the GeMS 'Topology Check' tool to identify potential attribution and geometry errors, and logical inconsistencies such as adjacency issues, and using the GeMS 'Validate Database' tool to identify errors related to the schema and content of the feature attribute tables and nonspatial tables. The data also were symbolized based on attributes (following the specifications in the FGDC Digital Cartographic Standard for Geologic Map Symbolization). The symbolized data was used to create the accompanying cartographic map product, which was visually inspected for errors and inconsistencies. This geodatabase is a composite geodataset that encapsulates the spatial and nonspatial data needed to depict and describe the geology of the map area, and to create the accompanying cartographic map product. The geodatabase conforms to the GeMS standard, except for deviations noted in the Data Quality section of the metadata record associated with each data element. The geodatabase contains all the schema and attribute elements required by the GeMS standard, unless otherwise noted in the Data Quality section of the metadata record associated with each data element. See LocationConfidenceMeters field in each feature attribute table for an estimation of horizontal positional accuracy. Field observations we made in May and September 2020; collection of samples for luminescence geochronology took place in May of 2020. Surficial geologic units were assigned names following an existing surficial geologic classification scheme based on the geomorphic depositional/erosional process, changes in deposit properties related to soil formation, post-depositional modification of the deposit surface, and inset relations. All observations were digitized in ArcGIS using USGS 3DEP lidar and the most recent imagery (e.g., NAIP imagery or Worldview-2 satellite imagery, both acquired in late 2019) as reference layers to aid in the placement of geologic features. Following data compilation and preparation of the accompanying map and text, the materials underwent five review cycles, including: (1) peer-review of the map and text for scientific integrity; (2) review of the text by staff in the California Water Science Center for consistency with their report guidelines and policies; (3) review of the text by staff in the Air Force Civil Engineering Corps; (4) digital review for database integrity, consistency of information between the database and accompanying materials (including metadata), and compliance to the GeMS standard, and; (5) editorial review for conformance to USGS publication standards. Unknown Universal Transverse Mercator 11 0.9996 -117.0 0.0 500000.0 0.0 coordinate pair 0.0001 0.0001 meters North American Datum of 1983 (NAD 83) Geodetic Reference System 1980 6378137 298.257222101 The geodatabase contains the following elements: nonspatial table DataSources (6 rows); nonspatial table DescriptionOfMapUnits (36 rows); nonspatial table GeoMaterialDict (101 rows); nonspatial table Glossary (23 rows); feature dataset GeologicMap which contains feature class ContactsAndFaults (2260 features), feature class GeologicLines (46 features), feature class MapUnitLabelPoints (842 features), feature class MapUnitPolys (842 features), feature class OrientationPoints (7 features), feature class GeochronPoints (4 features), and feature class Stations (1786 features). Detailed descriptions of entities, attributes, and attribute values are given in metadata for constituent elements of this composite dataset. "GeMS (Geologic Map Schema)--a standard format for digital publication of geologic maps", available at https://pubs.er.usgs.gov/publication/tm11B10. U.S. Geological Survey NGMDB mailing address

12201 Sunrise Valley Dr., MS 908

Reston VA 20192 United States ngmdb@usgs.gov Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data for other purposes, nor on all computer systems, nor shall the act of distribution constitute any such warranty. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Digital Data https://doi.org/10.5066/P9WTKPBP None 20230406 Andrew J Cyr U.S. Geological Survey, SOUTHWEST REGION Research Geologist physical

350 N Akron Rd

Moffett Field CA 94035 US 650-439-2820 acyr@usgs.gov FGDC Content Standard for Digital Geospatial Metadata FGDC-STD-001-1998