Pre-Upper Jurassic metamorphic rocks of the low-grade zone (WApJgs;0)

State	Washington
Name	Pre-Upper Jurassic metamorphic rocks of the low-grade zone
Geologic age	Early Cretaceous metamorphism (Jurassic protolith)
Original map label	pJgs
Primary rock type	greenschist
Secondary rock type	blueschist
Other rock types
Lithologic constituents	Major Metamorphic > Schist (Greenschist) Incidental Metamorphic > Schist (Glaucophane-schist)
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. Misch, P., 1979, Geologic Map of the Marblemount Quadrangle, Washington: Washington Division of Geology and Earth Resources Geologic Map GM-23, scale 1:48,000. Misch, P., 1977, Bedrock Geology of the North Cascades, in Brown, E. H. and Ellis, R. C. (eds.), Geological Excursions in the Pacific Northwest, Geological Society of America 1977 Annual Meeting, Seattle: Western Washington University, p. 1-62. Brown, E. H., Comparison of the Mineralogy and Phase Relations of Blueschists from the North Cascades, Washington, and Greenschists from Otago, New Zealand: Geological Society of America Bulletin, v. 85, no. 3, p. 333-344. 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. Duggan, K. M. and Brown, E. H., 1994, Correlation of the Tonga Formation and Chiwaukum Schist, North Cascades, Washington: Implications for Late Cretaceous orogenic mechanisms: Tectonics, v. 13, no. 6, p. 1411-1424.
Geographic coverage	Skagit - Whatcom