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Quantifying rock uplift rates using channel steepness and cosmogenic nuclide–determined erosion rates: Examples from northern and southern Italy

Rock uplift rates can be difficult to measure over 103–105 yr time scales. If, however, a landscape approaches steady state, where hillslope erosion and rock uplift rates are steady and locally similar, then it should be possible to quantify rock uplift rates from hillslope erosion rates. Here, we test this prediction by comparing channel steepness index values and 10Be catchment-averaged erosion
Authors
Andrew J. Cyr, Darryl E. Granger, Valerio Olivetti, Paola Molin

Geophysical framework of the northern San Francisco Bay region, California

We use geophysical data to examine the structural framework of the northern San Francisco Bay region, an area that hosts the northward continuation of the East Bay fault system. Although this fault system has accommodated ∼175 km of right-lateral offset since 12 Ma, how this offset is partitioned north of the bay is controversial and important for understanding where and how strain is accommodated
Authors
Victoria E. Langenheim, Russell W. Graymer, Robert C. Jachens, Robert J. McLaughlin, D.L. Wagner, Donald S. Sweetkind

Geometry and kinematics of the eastern Lake Mead fault system in the Virgin Mountains, Nevada and Arizona

The Lake Mead fault system is a northeast-striking, 130-km-long zone of left-slip in the southeast Great Basin, active from before 16 Ma to Quaternary time. The northeast end of the Lake Mead fault system in the Virgin Mountains of southeast Nevada and northwest Arizona forms a partitioned strain field comprising kinematically linked northeast-striking left-lateral faults, north-striking normal fa
Authors
Sue Beard, David J. Campagna, R. Ernest Anderson

Time-averaged paleomagnetic field at the equator: Complete data and results from the Galapagos Islands, Ecuador

We present here the complete paleomagnetic laboratory results from a collection of approximately 1500 oriented cores from all 16 of the Galapagos Islands, Ecuador, collected by Allan Cox in 1964–1965 but nearly all previously unpublished. The islands are located in the eastern Pacific Ocean within 1.4° of latitude from the equator and range in age from historically erupted to 3 Ma, mostly determin
Authors
Sherman Gromme, Edward A. Mankinen, Michel Prévot

Rapid middle Miocene extension and unroofing of the southern Ruby Mountains, Nevada

Paleozoic rocks in the northern Ruby Mountains were metamorphosed during Mesozoic crustal shortening and Cenozoic magmatism, but equivalent strata in the southern Ruby Mountains were never buried deeper than stratigraphic depths prior to exhumation in the footwall of a west dipping brittle normal fault. In the southern Ruby Mountains, Miocene sedimentary rocks in the hanging wall of this fault dat
Authors
Joseph Colgan, Keith A. Howard, Robert J. Fleck, Joseph L. Wooden

Adaptive management: The U.S. Department of the Interior technical guide

The purpose of this technical guide is to present an operational definition of adaptive management, identify the conditions in which adaptive management should be considered, and describe the process of using adaptive management for managing natural resources. The guide is not an exhaustive discussion of adaptive management, nor does it include detailed specifications for individual projects. Howe
Authors
B K Williams, Robert C. Szaro, Carl D. Shapiro

Quantifying the undiscovered geothermal resources of the United States

In 2008, the U.S. Geological Survey (USGS) released summary results of an assessment of the electric power production potential from the moderate- and high-temperature geothermal resources of the United States (Williams et al., 2008a; USGS Fact Sheet 2008-3082; http://pubs.usgs.gov/fs/2008/3082). In the assessment, the estimated mean power production potential from undiscovered geothermal resource
Authors
Colin F. Williams, Marshall J. Reed, Jacob DeAngelo, S. Peter Galanis

Digital coordinates and age for 3,869 foraminifer samples collected by Chevron Petroleum geologists in Washington and Oregon

The general location and age of more than 33,500 mostly foraminifer samples from Chevron Petroleum Company surface localities in California were provided by Brabb and Parker (2003, 2005). Malmborg and others (2008) provided digital latitude, longitude, and age for more than 13,000 of these samples. We provide here for the first time the digital latitude, longitude, and age for nearly 4,000 Chevron
Authors
William B. West, Earl E. Brabb, William T. Malmborg, John M. Parker

The Boring Volcanic Field of the Portland-Vancouver area, Oregon and Washington: Tectonically anomalous forearc volcanism in an urban setting

More than 80 small volcanoes are scattered throughout the Portland-Vancouver metropolitan area of northwestern Oregon and southwestern Washington. These volcanoes constitute the Boring Volcanic Field, which is centered in the Neogene Portland Basin and merges to the east with coeval volcanic centers of the High Cascade volcanic arc. Although the character of volcanic activity is typical of many mo
Authors
Russell C. Evarts, Richard M. Conrey, Robert J. Fleck, Jonathan T. Hagstrum

The Columbia River Basalt Group: from the gorge to the sea

Miocene flood basalts of the Columbia River Basalt Group inundated eastern Washington, Oregon, and adjacent Idaho between 17 and 6 Ma. Some of the more voluminous flows followed the ancestral Columbia River across the Cascade arc, Puget-Willamette trough, and the Coast Range to the Pacific Ocean. We have used field mapping, chemistry, and paleomagnetic directions to trace individual flows and flow
Authors
Ray E. Wells, Alan R. Niem, Russell C. Evarts, Jonathan T. Hagstrum

New Permian durhaminid cerioid corals from east-central California

Permian colonial corals from Artinskian to Kungurian strata in the Conglomerate Mesa area, Inyo Mountains, east-central California, include five new species, one of which is assigned to a new genus. The new taxa are: Malpaisia maceyi n. gen. and n. sp., Pararachnastraea bellula n. sp., P. delicata n. sp., P. owensensis n. sp., and Cordillerastraea inyoensis n. sp. These species, several of which c
Authors
C. H. Stevens, P. Stone

Magnetostratigraphic correlations of Permian-Triassic marine-to-terrestrial sections from China

We have studied three Permian–Triassic (PT) localities from China as part of a combined magnetostratigraphic, 40Ar/39Ar and U–Pb radioisotopic, and biostratigraphic study aimed at resolving the temporal relations between terrestrial and marine records across the Permo-Triassic boundary, as well as the rate of the biotic recovery in the Early Triassic. The studied sections from Shangsi (Sichuan Pro
Authors
J.M.G. Glen, S. Nomade, J.J. Lyons, I. Metcalfe, R. Mundil, P.R. Renne