U.S. Geological Survey Home AASG Logo USGS HOME CONTACT USGS SEARCH USGS
National Geologic Map Database
Geologic Units: Tonasket
Search archives
Map showing publication footprint
  • Usage in publication:
    • Tonasket Gneiss
  • Modifications:
    • First used
  • AAPG geologic province:
    • Okanogan province
Publication:

Snook, J.R., 1963, Petrology of parts of the Tonasket and Omak Lake quadrangles, north-central Washington: Dissertation Abstracts, v. 23, no. 8, p. 2878.


Summary:

First use of the Tonasket Gneiss. Consists of variable group of gently dipping banded migmatitic and feldspathic gneisses; basic gneisses; subordinate isochemically metamorphosed amphibolites and lime-silicate rocks and mylonitized derivatives of these rocks. Occurs north of the Patterson Lake Gneiss (new). Intruded by hypabyssal dike. (B1350)

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


Map showing publication footprint
  • Usage in publication:
    • Tonasket Gneiss
  • Modifications:
    • Named
  • Dominant lithology:
    • Gneiss
  • AAPG geologic province:
    • Okanogan province
Publication:

Snook, J.R., 1965, Metamorphic and structural history of "Colville batholith" gneisses, north-central Washington: Geological Society of America Bulletin, v. 76, no. 7, p. 759-776.


Summary:

Tonasket Gneiss is applied to gneisses previously described as "Coleville batholith" gneisses by Waters and Krauskopf (1941). Gneisses contain subordinate isochemical rocks, mainly amphibolites with small amounts of calcsilicate rocks; basic gneisses; highly variable group of migmatitic and feldspathic gneisses; and mylonitized derivatives of those rocks. Stratigraphic position of gneisses not yet determined because all boundaries are in fault contact with rocks of Triassic to Tertiary age. Tonasket Gneiss known to occupy area of at least 900 sq mi and is small part of plutonic complex that extends across northern Washington into Canada. (B1350)

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


Map showing publication footprint
  • Usage in publication:
    • Tonasket Gneiss*
  • Modifications:
    • Adopted
  • AAPG geologic province:
    • Okanogan province
Publication:

Fox, K.F., Jr., Rinehart, C.D., Engels, J.C., and Stern, T.W., 1976, Age of emplacement of the Okanogan gneiss dome, north-central Washington: Geological Society of America Bulletin, v. 87, no. 9, p. 1217-1224.


Summary:

Tonasket Gneiss of Snook (1965) is adopted and is restricted to layered gneiss. As such, it excludes the enveloping granitoid gneiss. Type area is designated. Age is Late Cretaceous.

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


Map showing publication footprint
  • Usage in publication:
    • Tonasket Gneiss*
  • Modifications:
    • Age modified
  • AAPG geologic province:
    • Okanogan province
Publication:

Fox, K.F., Jr., 1994, Geology of metamorphic core complexes and associated extensional structures in north-central Washington, IN Lasmanis, Raymond, and Cheney, E.S., convenors, Regional geology of Washington State: Washington Division of Geology and Earth Resources Bulletin, no. 80, p. 21-47.


Summary:

Age of the Tonasket Gneiss is Paleocene and early Eocene.

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


Search archives

For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.

Asterisk (*) indicates published by U.S. Geological Survey authors.

"No current usage" (†) implies that a name has been abandoned or has fallen into disuse. Former usage and, if known, replacement name given in parentheses ( ).

Slash (/) indicates name conflicts with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005, 2021). May be explained within brackets ([ ]).

Accessibility FOIA Privacy Policies and Notices

USA Gov U.S. Department of the Interior | U.S. Geological Survey
Supported by the National Cooperative Geologic Mapping Program
Page Contact Information: Personnel
Page Last Modified: Wed 12 Mar 2025 03:43:15 PM MDT