Publications
Publications from the staff of the Geology, Minerals, Energy, and Geophysics Science Center
Filter Total Items: 2354
Building on previous OSL dating techniques for gypsum: a case study from Salt Basin playa, New Mexico and Texas
The long term stability and reliability of the luminescence signal for gypsum has not been well documented or systematically measured until just recently. A review of the current literature for luminescence dating of gypsum is compiled here along with original efforts at dating an intact and in-situ bed of selenite gypsum at Salt Basin Playa, New Mexico and Texas. This effort differs from other do
Authors
Shannon Mahan, John Kay
Geophysical expression of elements of the Rio Grande rift in the northeast Tusas Mountains - Preliminary interpretations
New interpretations of the nature of the Rio Grande rift and pre-existing rocks in the northeast Tusas Mountains region are derived from new and existing gravity and aeromagnetic data. 12-15 mGal amplitude gravity lows are interpreted to mainly reflect large thicknesses of the upper Oligocene to upper Miocene, syn-rift Los Pinos Formation and possibly significant amounts of the Eocene El Rito Form
Authors
Benjamin J. Drenth, Kenzie J. Turner, Ren A. Thompson, V. J. Grauch, Michael A. Cosca, John Lee
Geochemical data from waters in Prospect Gulch, San Juan County, Colorado, that span pre- and post-Lark Mine remediation
In San Juan County, Colorado, the effects of historical mining continue to contribute dissolved metals to groundwater and surface water. Water samples in Prospect Gulch near Silverton, Colorado, were collected at selected locations that span pre- and post-reclamation activities at the Lark Mine, located in the Prospect Gulch watershed. Geochemical results from those water samples are presented in
Authors
Raymond H. Johnson, Douglas B. Yager, Hugh D. Johnson
The Hydrogeology of the San Juan Mountains Chapter 5
Knowledge of the occurrence, storage, and flow of groundwater in mountainous regions is limited by the lack of integrated data from wells, streams, springs, and climate. In his comprehensive treatment of the hydrogeology of the San Luis Valley, Huntley (1979) hypothesized that the underlying, fractured volcanic bedrock of the San Juan Mountains has relatively high bulk permeability and a regional-
Authors
Jonathan S. Caine, Anna B. Wilson
Results of time-domain electromagnetic soundings in Miami-Dade and southern Broward Counties, Florida
Time-domain electromagnetic (TEM) soundings were made in Miami-Dade and southern Broward Counties to aid in mapping the landward extent of saltwater in the Biscayne aquifer. A total of 79 soundings were collected in settings ranging from urban to undeveloped land, with some of the former posing problems of land access and interference from anthropogenic features. TEM soundings combined with monito
Authors
David V. Fitterman, Scott T. Prinos
Evaluation of landslide monitoring in the Polish Carpathians
In response to the June 15, 2010 request from the Polish Geological Institute (PGI) to the U.S. Geological Survey (USGS) for assistance and advice regarding real-time landslide monitoring, landslide specialists from the USGS Landslide Hazard Program visited PGI headquarters and field sites in September 2010. During our visit we became familiar with characteristics of landslides in the Polish Carpa
Authors
Brian D. Collins, Rex L. Baum, Teresa Mrozek, Piotr Nescieruk, Zbigniew Perski, Wojciech Raczkowski, Marek Graniczny
Value of a dual-polarized gap-filling radar in support of southern California post-fire debris-flow warnings
A portable truck-mounted C-band Doppler weather radar was deployed to observe rainfall over the Station Fire burn area near Los Angeles, California, during the winter of 2009/10 to assist with debris-flow warning decisions. The deployments were a component of a joint NOAA–U.S. Geological Survey (USGS) research effort to improve definition of the rainfall conditions that trigger debris flows from s
Authors
David P. Jorgensen, Maiana N. Hanshaw, Kevin M. Schmidt, Jayme L. Laber, Dennis M. Staley, Jason W. Kean, Pedro J. Restrepo
Hydrologic conditions and terrestrial laser scanning of post-firedebris flows in the San Gabriel Mountains, CA, U.S.A
To investigate rainfall-runoff conditions that generate post-wildfire debris flows, we instrumented and surveyed steep, small watersheds along the tectonically active front of the San Gabriel Mountains, California. Fortuitously, we recorded runoff-generated debris-flows triggered by one spatially restricted convective event with 28 mm of rainfall falling over 62 minutes. Our rain gages, nested hil
Authors
K. M. Schmidt, M. N. Hanshaw, J. F. Howle, J. W. Kean, Dennis M. Staley, J. D. Stock, W. Bawdeng
An empirical method to forecast the effect of storm intensity on shallow landslide abundance
We hypothesize that the number of shallow landslides a storm triggers in a landscape increases with rainfall intensity, duration and the number of unstable model cells for a given shallow landslide susceptibility model of that landscape. For selected areas in California, USA, we use digital maps of historic shallow landslides with adjacent rainfall records to construct a relation between rainfall
Authors
Jonathan D. Stock, Dino Bellugi
Helicopter electromagnetic and magnetic geophysical survey data, Hunton anticline, south-central Oklahoma
This report is a digital data release for multiple geophysical surveys conducted in the Hunton anticline area of south-central Oklahoma. The helicopter electromagnetic and magnetic surveys were flown on March 16–17, 2007, in four areas of the Hunton anticline in south-central Oklahoma. The objective of this project is to improve the understanding of the geohydrologic framework of the Arbuckle-Simp
Authors
Bruce D. Smith, David V. Smith, Maryla Deszcz-Pan, Charles D. Blome, Patricia Hill
Cenozoic tectonic reorganizations of the Death Valley region, southeast California and southwest Nevada
The Death Valley region, of southeast California and southwest Nevada, is distinct relative to adjacent regions in its structural style and resulting topography, as well as in the timing of basin-range extension. Cenozoic basin-fill strata, ranging in age from greater than or equal to 40 to approximately 2 million years are common within mountain-range uplifts in this region. The tectonic fragment
Authors
Christopher J. Fridrich, Ren A. Thompson
A dryland river transformed—the Little Colorado, 1936–2010
The Little Colorado River, in northeastern Arizona, is a major tributary of the Colorado River. Over a span of 74 years, the U.S. Geological Survey (USGS) has mapped substantial migration of the river channel between the City of Winslow and the Navajo Nation community of Leupp (Tólchíí kooh). In a human lifetime, the river has moved more than 1 mile across its valley floor. Channel migration and f
Authors
Debra L. Block, Margaret Hiza Redsteer