Physical Sciences and Mathematics Commons^™

A Robust Age Model For The Cryogenian Pocatello Formation Of Southeastern Idaho (Northwestern Usa) From Tandem In Situ And Isotope Dilution U-Pb Dating Of Volcanic Tuffs And Epiclastic Detrital Zircons, Vincent H. Isakson, Mark D. Schmitz, Carol M. Dehler, Francis A. Macdonald, W. Adolph Yonkee

Geosciences Faculty Publications and Presentations

Tandem in situ and isotope dilution U-Pb analysis of zircons from pyroclastic volcanic rocks and both glacial and non-glacial sedimentary strata of the Pocatello Formation (Idaho, northwestern USA) provides new age constraints on Cryogenian glaciation in the North American Cordillera. Two dacitic tuffs sampled within glacigenic strata of the lower diamictite interval of the Scout Mountain Member yield high-precision chemical abrasion isotope dilution U-Pb zircon eruption and depositional ages of 696.43 ± 0.21 and 695.17 ± 0.20 Ma. When supplemented by a new high-precision detrital zircon maximum depositional age of ≤ 670 Ma for shoreface and offshore sandstones unconformably overlying …

Structural Geology Of The Northern Part Of Elkhorn Mountain, Bannock Range, Idaho, Stephen R. Crook

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Northern Elkhorn Mountain was unmapped previous to this investigation. The mapped area is located north of Malad City, Idaho, in the Bannock Range. It is within the Basin and Range Province. The mapped area measures 5.4 mi. in the north-south direction and 8.9 mi. in the east-west direction.

The oldest exposed stratigraphic unit, within the mapped area, consists of orthoquartzite and is of Early Cambrian age. Cambrian formations of the mapped area, in ascending order, are as follows: Camelback Mountain Quartzite, Gibson Jack Formation, Elkhead Formation, Bloomington Formation, Nounan Formation, and St. Charles Formation. Units of Ordovician age are the …