Unit symbol: | JIPe |
---|---|
Age range | Middle Jurassic to Pennsylvanian (323.2 to 168.3 Ma) |
Lithology: | Sedimentary |
Group name: | Etivluk Group, undivided |
Source map | Ellersieck, Inyo, Curtis, S.M., Mayfield, C.F., and Tailleur, I.L., 1990, Reconnaissance geologic map of the De Long Mountains A-2 and B-2 quadrangles and part of the C-2 quadrangle, Alaska: U.S. Geological Survey Miscellaneous Investigations Series Map I-1931, 2 sheets, scale 1:63,360. |
---|---|
Symbol | JIPe1 |
Unit name | Etivluk Group |
Description | Gray chert with minor amounts of shale; weathers brown, yellow, gray, green, and maroon. Consists of the Siksikpuk and Otuk Formations. Part of the Brooks Range allochthon, Key Creek sequence. |
Lithology | Sedimentary |
Label | Pzeg |
---|---|
Description | Etivluk Group, undivided: Includes Siksikpuk and Otuk Formations and underlying Immaitchiak Chert |
Geologic age | Pennsylvanian to Bajocian |
Geologic setting | Sedimentary, slope-and-deep-water |
Lithology | Form | Importance |
---|---|---|
Chert < Chemical < Sedimentary | Bed | Major |
Graywacke < Sandstone < Clastic < Sedimentary | Carbonaceous | Indeterminate, major |
Argillite < Metaclastic < Metasedimentary < Metamorphic | Zeolitic (prehnite-pumpellyite) | Minor |
Shale < Mudstone < Clastic < Sedimentary | Carbonaceous | Minor |
Limestone < Carbonate < Sedimentary | Bed | Incidental |