|Name||Cretaceous sedimentary rocks, mostly marine|
Sedimentary > Clastic > Sandstone > Arkose (Bed)
Sedimentary > Clastic > Mudstone > Shale > Black-shale (Bed)
Metamorphic > Metasedimentary > Metaclastic > Phyllite
Sedimentary > Clastic > Conglomerate (Bed)
|Comments||Huntting and others, 1961, (source map) references a 1958 unpublished map by Barksdale when including the Virginian Ridge Formation in this unit but more recent mapping by Barksdale (1975) shows that most of the Virginian Ridge Formation is actually in Huntting's WAKu unit (Winthrop Sandstone). Goat Creek Formation is 5120 ft thick, mostly arkose (80%), black shale (20%) and incidental conglomerate; Panther Creek Formation is 5200 ft thick, mostly black shale (90%), conglomerate (6%), and arkose (4%); Harts Pass Formation is 7900 ft thick, mostly arkose (70%) and black shale (30%) (Barksdale, 1975--NOTE: uses black shale interchangeably with argillite).|
|Stratigraphic units||Virginian Ridge Formation (in part); Harts Pass Formation; Panther Creek Formation; Goat Creek Formation; Jack Mountain Phyllite|
Huntting, M.T., Bennett, W.A.G., Livingston, V.E.Jr., and Moen, W.S., 1961, Geologic Map of Washington: Washington Division of Mines and Geology, scale 1:500,000.
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.
Barksdale, J.D., 1975, Geology of the Methow Valley, Okanogan County, Washington: Washington Division of Geology and Earth Resources Bulletin no. 48, 72 p.
|Counties||Okanogan - Skagit - Whatcom|