Pre-Middle Jurassic sedimentary and volcanic rocks (WApJ;0)

State	Washington
Name	Pre-Middle Jurassic sedimentary and volcanic rocks
Geologic age	Late Paleozoic deposition? with Cretaceous metamorphism?
Original map label	pJ
Comments	Original sedimentary and volcanic rocks are largely deformed and metamorphosed Tertiary plutonism destroyed greenschist facies minerals and now many rocks are pyroxene hornfels (Tabor and others, 1993).
Primary rock type	chert
Secondary rock type	metavolcanic rock
Other rock types	argillite; graywacke; metasedimentary rock; quartzite; conglomerate
Lithologic constituents	Major Metamorphic > Metavolcanic (Greenschist)Includes spilite, greenstone, meta-andesite and meta-basalt. Sedimentary > Chemical > Chert (Bed) Minor Sedimentary > Clastic > Sandstone > Graywacke (Bed) Metamorphic > MetasedimentaryIncludes metagraywacke, "metagrit", meta-conglomerate, and slate. Metamorphic > ArgilliteCalcareous; grades into phyllitic slate in north King County; black in Skagit County. Incidental Sedimentary > Clastic > Conglomerate (Bed) Metamorphic > QuartziteMeta-chert.
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. Tabor, R. W., Frizzell, V. A., Jr., Booth, D. B., Waitt, R. B., Whetten, J. T., Zartman, R. E., 1993, Geologic Map of the Skykomish River 30- by 60-Minute Quadrangle, Washington: U. S. Geological Survey Miscellaneous Investigations Series Map I-1963, scale 1:100,000. [http://pubs.er.usgs.gov/publication/i1963] 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. Tabor, R. W., Booth, D. B., Vance, J. A., Ford, A. B., Ort, M. H., 1988, Preliminary geologic map of the Sauk River 30 by 60 minute quadrangle, Washington: U. S. Geological Survey Open File Report 88-692, 51 p., 1 pl. [http://pubs.er.usgs.gov/publication/ofr88692]
Geographic coverage	King - Skagit - Snohomish