Pre-Tertiary metamorphic rocks, undivided (WApTm;0)

State	Washington
Name	Pre-Tertiary metamorphic rocks, undivided
Geologic age	Probably Permian
Original map label	pTm
Comments	Outcrops in Okanogan County are mostly metasedimentary rocks, including metawacke, metalimestone, metadolostone, metasiltite, meta-argillite, and metaconglomerate, as well as black slate, phyllite, gneiss, schist, quartzite, amphibolite, and greenstone; outcrops near Spokane consist of phyllite, metalimestone, quartzite, and metasiltite, with alteration to calc-silicate rocks, schist, marble, and hornfels (Stoffel and others, 1991). Tonalite and gabbro in San Juan Islands and possibly in Chelan County (Brandon, 1989)
Primary rock type	metasedimentary rock
Secondary rock type	schist
Other rock types	gneiss; marble; quartzite; amphibolite; greenstone; phyllite; calc-silicate rock; slate; limestone; tonalite; gabbro; hornfels
Lithologic constituents	Major Metamorphic > MetasedimentaryIncludes metaconglomerate, meta-argillite, metawacke, metalimestone, metadolostone, and metasiltite (metasiltstone). Minor Metamorphic > Gneiss Metamorphic > Schist Incidental Metamorphic > Hornfels Igneous > Plutonic > Gabbroic > Gabbro (Pluton) Igneous > Plutonic > Granitic > Tonalite (Pluton) Sedimentary > Carbonate > Limestone (Lense) Metamorphic > Slate Metamorphic > PhyllitePossibly minor in rank. Metamorphic > Greenstone Metamorphic > Amphibolite Metamorphic > QuartzitePossibly minor in rank. Metamorphic > MarblePossibly minor in rank.
Map references	Huntting, M. T., Bennett, W. A. G., Livingston, V. E. Jr., Moen, W. S., 1961, Geologic Map of Washington: Washington Division of Mines and Geology, scale 1:500,000.
Unit references	Huntting, M. T., Bennett, W. A. G., Livingston, V. E. Jr., Moen, W. S., 1961, Geologic Map of Washington: Washington Division of Mines and Geology, scale 1:500,000. Stoffel, K. L., Joseph, N. L., Waggoner, S. Z., Gulick, C. W., Korosec, M. A., Bunning, B. B., 1991, Geologic Map of Washington--Northeast Quadrant: Washington Division of Geology and Earth Resources Geologic Map, GM-39, scale 1:250,000. Brandon, M. T., 1989, Geology of the San Juan-Cascade Nappes, northwestern Cascade Range and San Juan Islands, in Joseph, N. L. (Ed.), Geologic Guidebook for Washington and Adjacent Areas: prepared for the 85th Annual Meeting of the Cordilleran Section, Geological Society of America, May 8-11, 1989, Spokane, Washington: Washington Division of Geology and Earth Resource Infomation Circular 86, p. 137-162. Rinehart, C. D., and Fox, K. F., Jr., 1972, Geology and Mineral Deposits of the Loomis Quadrangle, Okanogan County, Washington: Washington Division of Mines and Geology Bulletin No. 64, 124 p. Dragovich, J. D., Logan, R. L., Schasse, H. W., Walsh, T. J., Lingley, W. S., Jr., Norman, D. K., Gerstel, W. J., Lapen, T. J., Schuster, J. E., Meyers, K. D., 2002, Geologic Map of Washington-Northwest Quadrant: Washington Division of Geology and Earth Resources Geologic Map GM-50, scale 1:250,000.
Geographic coverage	Chelan - Lincoln - Okanogan - San Juan - Skagit - Spokane - Stevens - Whatcom