Publications

Variations in the geochemistry of rocks from the Meade Peak Member of the Phosphoria Formation were examined using ratios of elements associated with either the +terrigenous or marine sediment fractions. Inter-element relationships in the terrigenous fraction appear useful for chemo-stratigraphic correlation. A sharp decrease upsection in K2O/AI2O3 ratios occurs in the lower half of all but the mo

The Western Phosphate Field (WPF), composed of Permian marine sedimentary strata that cover over 300,000 km2 in the middle Rocky Mountains of Idaho, Montana, Utah, and Wyoming in the United States, contains vast resources of phosphate mined for fertilizer and a range of other industrial applications. The richest deposits of phosphate in the WPF occur in the Meade Peak Phosphatic Shale Member of th

Beneath the Arctic coastal plain (commonly referred to as "the 1002 area") in the Arctic National Wildlife Refuge, northeastern Alaska, United States, seismic reflection data show that the northernmost and youngest part of the Brookian orogen is preserved as a Paleogene to Neogene system of blind and buried thrust-related structures. These structures involve Proterozoic to Miocene (and younger?) r

The Humboldt River Basin is an arid to semiarid, internally drained basin that covers approximately 43,000 km2 in northern Nevada. The basin contains a wide variety of metallic and nonmetallic mineral deposits and occurrences, and, at various times, the area has been one of the Nation's leading or important producers of gold, silver, copper, mercury, and tungsten. Nevada currently (2003) is the th

High-resolution seismic-reflection data are combined with a variety of other geophysical and geological data to interpret the offshore structure and earthquake hazards of the San Pedro shelf, near Los Angeles, California. Prominent structures investigated include the Wilmington graben, the Palos Verdes fault zone, various faults below the west part of the San Pedro shelf and slope, and the deep-wa

The Coast Range ophiolite of California is one of the most extensive ophiolite terranes in North America, extending over 700 km from the northernmost Sacramento Valley to the southern Transverse Ranges in central California. This ophiolite, and other ophiolite remnants with similar mid-Jurassic ages, represent a major but short-lived episode of oceanic crust formation that affected much of western

New SHRIMP (sensitive, high-resolution ion microprobe) U-Pb zircon ages and trace element geochemical data for mafic and felsic metaigneous rocks of the pericratonic Yukon-Tanana terrane in east-central Alaska help define the tectonic setting of mid-Paleo-zoic magmatism and syngenetic hydrothermal Zn-Pb-Ag mineralization along the ancient Pacific margin of North America. We compare data from simil

Geophysical information, including deep-crustal seismic reflection, magnetotelluric (MT), gravity, and magnetic data, cross the aftershock zone of the 3 November 2002 Mw 7.9 Denali fault earthquake. These data and aftershock seismicity, jointly interpreted, reveal the crustal structure of the right-lateral-slip Denali fault and the eastern Alaska Range orogen, as well as the relationship between t

We present photomosaics and logs of the walls of trenches excavated for a paleoseismic study at Mill Canyon, one of two sites along the San Andreas fault in the Santa Cruz Mtns. on the Kelley-Thompson Ranch. This site was a part of Rancho Salsipuedes beginning in 1834. It was purchased by the present owner’s family in 1851. Remnants of a cabin/mill operations still exist up the canyon dating from

Predictions of waste canister and repository driftwall temperatures as functions of space and time are important to evaluate pre-closure performance of the proposed repository for spent nuclear fuel and high-level radioactive waste at Yucca Mountain, Nevada. Variations in the lithostratigraphic features in densely welded and crystallized rocks of the 12.8-million-year-old Topopah Spring Tuff, espe

No abstract available.

No abstract available.