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Publications

Publications from the staff of the Geology, Minerals, Energy, and Geophysics Science Center

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Dust and human health

It is generally accepted that exposure to fine particulate matter may increase risk for human morbidity and mortality. Until recently, population health related studies examining the effects of particulate matter on human health generally examined anthropogenic (industry and combustion by-products) sources with few studies considering contributions from natural sources. This chapter provides an ov
Authors
Suzette A. Morman, Geoffrey S. Plumlee

Stratigraphy and paleogeographic significance of the Pennsylvanian-Permian Bird Spring Formation in the Ship Mountains, southeastern California

A thick sequence of limestone, dolomite, and minor sandstone assigned to the Pennsylvanian and lower Permian Bird Spring Formation is exposed in the Ship Mountains about 85 kilometers (km) southwest of Needles, California, in the eastern Mojave Desert. These strata provide a valuable reference section of the Bird Spring Formation in a region where rocks of this age are not extensively exposed. Thi
Authors
Paul Stone, Calvin H. Stevens, Keith A. Howard, Thomas D. Hoisch

Hysteresis of unsaturated hydromechanical properties of a silty soil

Laboratory tests to examine hysteresis in the hydrologic and mechanical properties of partially saturated soils were conducted on six intact specimens collected from a landslide-prone area of Alameda County, California. The results reveal that the pore-size distribution parameter remains statistically unchanged between the wetting and drying paths; however, the wetting or drying state has a pronou
Authors
Ning Lu, Murat Kaya, Brian D. Collins, Jonathan W. Godt

Zinc isotope and transition-element dynamics accompanying hydrozincite biomineralization in the Rio Naracauli, Sardinia, Italy

The Rio Naracauli in SW Sardinia drains part of the Ingurtosu Zn–Pb mining district, and contains extreme concentrations of dissolved Zn at near-neutral pH. In the upper reaches of the stream, pH, alkalinity and Zn concentrations are such that hydrozincite [Zn5(CO3)2(OH)6] precipitates in a biologically mediated process facilitated by a microalga (Chlorella sp.) and a cyanobacterium (Scytonema sp.
Authors
Richard B. Wanty, F. Podda, Giovanni De Giudici, R. Cidu, Pierfranco Lattanzi

Reactivation of the Archean-Proterozoic suture along the southern margin of Laurentia during the Mazatzal orogeny: Petrogenesis and tectonic implications of ca. 1.63 Ga granite in southeastern Wyoming

The presence of ca. 1.63 Ga monzogranite (the “white quartz monzonite”) in the southern Sierra Madre, southeastern Wyoming, is anomalous given its distance from the nearest documented plutons of similar age (central Colorado) and the nearest contemporaneous tectonic margin (New Mexico). It is located immediately south of the Cheyenne belt—a ca. 1.75 Ga Archean-Proterozoic tectonic suture. New geoc
Authors
Daniel S. Jones, Calvin G. Barnes, Wayne R. Premo, Arthur W. Snoke

Paleogeographic insights based on new U-Pb dates for altered tuffs in the Miocene Barstow Formation, California

The type section of the Barstow Formation in the Mud Hills, north of Barstow, is a reference section for early to middle Miocene paleontology, magnetostratigraphy, and dated volcanic episodes. Thanks to this robust chronologic framework, much of the interpretation of the paleogeography of the region from about 18 Ma to 13 Ma is based on study of the rocks in the Mud Hills. Eastward from the type s
Authors
David M. Miller, Jose E. Rosario, Shannon R. Leslie, Jorge A. Vazquez

The Idaho cobalt belt

The Idaho cobalt belt (ICB) is a northwest-trending belt of cobalt (Co) +/- copper (Cu)-bearing deposits and prospects in the Salmon River Mountains of east-central Idaho, U.S.A. The ICB is about 55 km long and 10 km long in its central part, which contains multiple strata-bound ore zones in the Blackbird mine area. The Black Pine and Iron Creek Co-Cu prospects are southeast of Blackbird, and the
Authors
Arthur A. Bookstrom

Field guide to selected sites along the Idaho Cobalt Belt (ICB) and to the Beartrack Gold Deposit, in the eastern Salmon River Mountains

This field guide provides a road log to and geologic descriptions of selected sites in the Idaho cobalt belt, and at the Beartrack gold mine, in the eastern Salmon River Mountains.
Authors
Arthur A. Bookstrom, George King, Robert A. Perry, John Childs

Unique challenges facing Southwestern tribes: Chapter 17

Executive Summary When considering climate change, risks to Native American lands, people, and cultures are noteworthy. Impacts on Native lands and communities are anticipated to be both early and severe due to their location in marginal environments. Because Native American societies are socially, culturally, and politically unique, conventional climate change adaptation planning and related poli
Authors
Margaret Hiza, Karletta Chief, Kirk Bemis, Mahesh Gautam, Beth Rose Middleton, Rebecca Tsosie

Geophysical constraints on Rio Grande rift structure and stratigraphy from magnetotelluric models and borehole resistivity logs, northern New Mexico

Two- and three-dimensional electrical resistivity models derived from the magnetotelluric method were interpreted to provide more accurate hydrogeologic parameters for the Albuquerque and Española Basins. Analysis and interpretation of the resistivity models are aided by regional borehole resistivity data. Examination of the magnetotelluric response of hypothetical stratigraphic cases using resist
Authors
Brian D. Rodriguez, David A. Sawyer

Monte Carlo simulations of product distributions and contained metal estimates

Estimation of product distributions of two factors was simulated by conventional Monte Carlo techniques using factor distributions that were independent (uncorrelated). Several simulations using uniform distributions of factors show that the product distribution has a central peak approximately centered at the product of the medians of the factor distributions. Factor distributions that are peaked
Authors
Mark E. Gettings

Overcoming the momentum of anachronism: American geologic mapping in a twenty-first-century world

The practice of geologic mapping is undergoing conceptual and methodological transformation. Profound changes in digital technology in the past 10 yr have potential to impact all aspects of geologic mapping. The future of geologic mapping as a relevant scientific enterprise depends on widespread adoption of new technology and ideas about the collection, meaning, and utility of geologic map data. I
Authors
Kyle House, Ryan Clark, Joe Kopera