Shale, arenite, conglomerate, intermediate and felsic volcanic rocks; Late Proterozoic rifted continental margin; southeastern Idaho (IDZ1s;0)

State	Idaho
Name	Shale, arenite, conglomerate, intermediate and felsic volcanic rocks; Late Proterozoic rifted continental margin; southeastern Idaho
Geologic age	Late Proterozoic
Original map label	Z1s
Comments	Z1s unit includes Late Proterozic Pocatello Fm, which underlies the Late Proterozoic to Cambrian Brighamn Group. Rhyolite clasts of the bimodal Bannock Volcanic Member (dated 717 +/- 4 Ma) are included in Sturtian glaciogenic diamictite of the Scout Mountain Member. A tuff bed in the uppermost Scout Mountain Mbr was dated 667 +/- 5 Ma (ID144). Glaciogenic diamictite is capped by post-glacial carbonate.
Primary rock type	shale
Secondary rock type	arenite
Other rock types	conglomerate; bimodal suite; intermediate metavolcanic rock; meta-rhyolite; lava flow; pyroclastic
Lithologic constituents	Major Sedimentary > Clastic > Mixed-clastic > Siltstone-Mudstone (Bed)black shale, slate, argillite, siltite Minor Igneous > Volcanic > Mafic-volcanic > Andesite (Flow)greenstone after quartz andesite flows of Bannock Member Sedimentary > Clastic > Conglomerate (Bed)glaciogenic diamictite of Scout Mtn Member Sedimentary > Clastic > Sandstone > Arenite (Bed)quartzite Incidental Igneous > Volcanic > Felsic-volcanic > Rhyolite (Pyroclastic)rhyolite porphyry clast (717 Ma), upper Scout Mtn Mbr Igneous > Volcanic > Mafic-volcanic > Andesite (Pyroclastic, air fall)green reworked fallout tuff (667 Ma) upper Scout Mtn Mbr Igneous > Volcanic > Mafic-volcanic > Andesite (Pyroclastic)plagioclase-phyric tuff breccia (717 Ma) lower Scout Mtn Mbr
Map references	Bond, J.G., Kauffman, J.D., Miller, D.A., and Venkatakrishnan, Ramesh, 1978, Geologic map of Idaho: Moscow, Idaho, Idaho Bureau of Mines and Geology, with contributions from U.S. Geological Survey, scale 1:500,000.
Unit references	Bond, J.G., Kauffman, J.D., Miller, D.A., and Venkatakrishnan, Ramesh, 1978, Geologic map of Idaho: Moscow, Idaho, Idaho Bureau of Mines and Geology, with contributions from U.S. Geological Survey, scale 1:500,000. Rember, W.C., and Bennett, E.H., 1979, Geologic map of the Pocatello quadrangle, Idaho: Moscow, Idaho, Idaho Bureau of Mines and Geology, Geologic Map Series, Pocatello 2o quadrangle, scale 1:250,000. Crittenden, M.D., Schaeffer, F.E., Trimble, D.E., and Woodward, L.A., 1971, Nomenclature and correlations of some upper Precambrian and basal Cambrian sequences in western Utah and southeastern Idaho: Geological Society of America Bulletin, v. 82, no. 3, p. 581-602. Ludlum, J.C., 1942, Pre-Cambrian formatisons at Pocatello Idaho: Journal of Geology, v. 50, no. 1, p. 85-95. Fanning, M.C., and Link, P.K., 2004, U-Pb SHRIMP ages of Neoproterozoic (Sturtian) glaciogenic Pocatello Formation, southeastern Idaho: Geology, v. 32, no. 10, p. 881-884.
Geographic coverage	Bannock