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Map showing publication footprint
  • Usage in publication:
    • Silver Pass volcanics
  • Modifications:
    • First used
  • AAPG geologic province:
    • Cascades province
Publication:

Foster, R.J., 1957, Tertiary geology of a portion of the central Cascade Mountains, Washington: Dissertation Abstracts, v. 17, no. 9, p. 1982.


Summary:

First use of the name Silver Pass volcanics. Consists of andesite flows. Unconformably overlies the Swauk arkose; unconformably underlies the Teanaway basalt. Age is Tertiary.

Source: GNU records (USGS DDS-6; Menlo GNULEX).


Map showing publication footprint
  • Usage in publication:
    • Silver Pass volcanic rocks
  • Modifications:
    • Named
  • Dominant lithology:
    • Andesite
    • Tuff
    • Breccia
  • AAPG geologic province:
    • Cascades province
Publication:

Foster, R.J., 1960, Tertiary geology of a portion of the central Cascade Mountains, Washington: Geological Society of America Bulletin, v. 71, no. 2, p. 99-126, (incl. geologic map, scale 1:125,000)


Summary:

Silver Pass volcanics (Foster, 1957) is named the Silver Pass volcanic rocks. Is named for Silver Pass, Kittitas Co., WA. Includes rocks previously assigned to the Kachess rhyolite (Smith and Calkins, 1906). Consists of lava, pyroclastic rocks, and volcanic sedimentary rocks. The unit is heterogeneous and is characterized by abrupt horizontal and vertical changes in rock type. Overlies the Easton schist in the type area; elsewhere overlies the Swauk formation; underlies the Teanaway basalt. At Silver Pass is intruded by basaltic dikes that are presumably the Teanaway dike swarm. Age is Paleocene or Eocene (Eocene? on map).

Source: GNU records (USGS DDS-6; Menlo GNULEX).


Map showing publication footprint
  • Usage in publication:
    • Silver Pass Volcanic Rocks*
  • Modifications:
    • Geochronologic dating
  • AAPG geologic province:
    • Cascades province
Publication:

Tabor, R.W., Waitt, R.B., Jr., Frizzell, V.A., Jr., Swanson, D.A., Byerly, G.R., and Bentley, R.D., 1982, Geologic map of the Wenatchee 1:100,000 quadrangle, central Washington: U.S. Geological Survey Miscellaneous Investigations Series Map, I-1311, 1 sheet, 26 p., scale 1:100,000 [http://ngmdb.usgs.gov/Prodesc/proddesc_9137.htm]


Summary:

Silver Pass Volcanic Rocks of Foster (1960) are early Eocene based on a fission-track (zircon) date of 50.4 Ma on rocks in the near Liberty; similar tuffs have fission-track dates of 50.5, 48.6, and 43.6 Ma. Silver Pass rocks exposed of the Wenatchee sheet (1:100,000) have fission-track (zircon) dates of 53 +/-5 and 51 +/-5 Ma.

Source: GNU records (USGS DDS-6; Menlo GNULEX).


Map showing publication footprint
  • Usage in publication:
    • Silver Pass Volcanic Member*
  • Modifications:
    • Adopted
    • Revised
  • AAPG geologic province:
    • Cascades province
Publication:

Tabor, R.W., Frizzell, V.A., Jr., Vance, J.A., and Naeser, C.W., 1984, Ages and stratigraphy of lower and middle Tertiary sedimentary and volcanic rocks of the central Cascades, Washington; application to the tectonic history of the Straight Creek Fault: Geological Society of America Bulletin, v. 95, no. 1, p. 26-44.


Summary:

Silver Pass volcanic rocks (Foster, 1960) are adopted as the Silver Pass Volcanic Member of the Swauk Formation. Thickness is about 1,800 m. Age is Eocene [text states early Eocene based on fission-track dates in Table 2; figure 7 shows age as early and middle Eocene].

Source: GNU records (USGS DDS-6; Menlo GNULEX).


Map showing publication footprint
  • Usage in publication:
    • Silver Pass Member*
Publication:

Tabor, R.W., Frizzell, V.A., Jr., Booth, D.B., Waitt, R.B., Whetten, J.T., and Zartman, R.E., 1993, Geologic map of the Skykomish River 30' x 60' quadrangle, Washington: U.S. Geological Survey Miscellaneous Investigations Series Map, I-1963, 1 sheet, 42 p., scale 1:100,000 [http://ngmdb.usgs.gov/Prodesc/proddesc_10042.htm]


Summary:

Not compiled to date. Publication available online: http://ngmdb.usgs.gov/Prodesc/proddesc_10042.htm
Silver Pass Member of Swauk Formation. Age is early Eocene.

Source: Publication.


Map showing publication footprint
  • Usage in publication:
    • Silver Pass Volcanic Member*
  • Modifications:
    • Areal extent
  • AAPG geologic province:
    • Cascades province
Publication:

Tabor, R.W., Frizzell, V.A., Booth, D.B., and Waitt, R.B., 2000, Geologic map of the Snoqualmie Pass 30' x 60' quadrangle, Washington; Version 1.0: U.S. Geological Survey Miscellaneous Investigations Series Map, I-2538, 1 sheet, 57 p., scale 1:100,000 [http://ngmdb.usgs.gov/Prodesc/proddesc_37097.htm]


Summary:

Silver Pass Volcanic Member of the Swauk Formation if geographically extended into the report area. Age is early Eocene.

Source: GNU records (USGS DDS-6; Menlo GNULEX).


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