Evidence for slip partitioning and bimodal slip behavior on a single fault: Surface slip characteristics of the 2013 Mw7.7 Balochistan, Pakistan earthquake
William D. Barnhart, Richard W. Briggs, Nadine G. Reitman, Ryan D. Gold, Gavin P. Hayes
2015, Earth and Planetary Science Letters (420) 1-11
Deformation is commonly accommodated by strain partitioning on multiple, independent strike-slip and dip-slip faults in continental settings of oblique plate convergence. As a corollary, individual faults tend to exhibit one sense of slip – normal, reverse, or strike-slip – until whole-scale changes in boundary conditions reactivate preexisting faults in a...
Time-varying interseismic strain rates and similar seismic ruptures on the Nias-Simeulue patch of the Sunda megathrust
Aron J. Meltzner, Kerry E. Sieh, Hong-Wei Chiang, Chung-Che Wu, Louisa L.H. Tsang, Chuan-Chou Shen, Emma M. Hill, Bambang W. Suwargadi, Danny H. Natawidjaja, Belle Philibosian, Richard W. Briggs
2015, Quaternary Science Reviews (122) 258-281
Fossil coral microatolls from fringing reefs above the great (MW 8.6) megathrust rupture of 2005 record uplift during the historically reported great earthquake of 1861. Such evidence spans nearly the entire 400-km strike length of the 2005 rupture, which was previously shown to be bounded by two persistent barriers...
Slip-pulse rupture behavior on a 2 meter granite fault
Gregory C. McLaskey, Brian D. Kilgore, Nicholas M. Beeler
2015, Geophysical Research Letters (42) 7039-7045
We describe observations of dynamic rupture events that spontaneously arise on meter-scale laboratory earthquake experiments. While low-frequency slip of the granite sample occurs in a relatively uniform and crack-like manner, instruments capable of detecting high frequency motions show that some parts of the fault slip abruptly (velocity >100 mm∙s-1, acceleration...
Evaluation of vector coastline features extracted from 'structure from motion'-derived elevation data
Nicole Kinsman, Ann E. Gibbs, Matt Nolan
2015, Conference Paper, Proceedings of the Coastal Sediments 2015
For extensive and remote coastlines, the absence of high-quality elevation models—for example, those produced with lidar—leaves some coastal populations lacking one of the essential elements for mapping shoreline positions or flood extents. Here, we compare seven different elevation products in a lowlying area in western Alaska to establish their appropriateness...
Algoma-, Superior-, and oolitic-type iron deposits of the Islamic Republic of Mauritania (phase V, deliverable 83)
Cliff D. Taylor, Carol A. Finn, Eric D. Anderson, M. Y. Joud, M. A. Taleb, John D. Horton
2015, Open-File Report 2013-1280-O
High-grade hematitic iron ores (or HIF, containing 60–65 percent Fe) have been mined in Mauritania from Superior-type iron deposits since 1952. Depletion of the high grade ores in recent years has resulted in a number of new projects focused on lower grade magnetite ores in Algoma-type banded iron formation (or...
Quantifying stream thermal regimes at management-pertinent scales: combining thermal infrared and stationary stream temperature data in a novel modeling framework.
Shane J. Vatland, Robert E. Gresswell, Geoffrey C. Poole
2015, Water Resources Research (51) 31-46
Accurately quantifying stream thermal regimes can be challenging because stream temperatures are often spatially and temporally heterogeneous. In this study, we present a novel modeling framework that combines stream temperature data sets that are continuous in either space or time. Specifically, we merged the fine spatial resolution of thermal infrared...
Micrometer-scale U–Pb age domains in eucrite zircons, impact re-setting, and the thermal history of the HED parent body
M.D. Hopkins, S.J. Mojzsis, W.F. Bottke, Oleg Abramov
2015, Icarus (245) 367-378
Meteoritic zircons are rare, but some are documented to occur in asteroidal meteorites, including those of the howardite–eucrite–diogenite (HED) achondrite clan (Rubin, A. [1997]. Meteorit. Planet. Sci. 32, 231–247). The HEDs are widely considered to originate from the Asteroid 4 Vesta. Vesta and the other large main belt asteroids record...
Dispersal, movements and site fidelity of post-fledging King Eiders Somateria spectabilis and their attendant females
Rebecca L. Bentzen, Abby N. Powell
2015, Ibis (157) 133-146
Post-fledging dispersal and site fidelity are poorly understood, particularly for sea ducks that spend the majority of their annual cycle at sea. This is the first description of movements and their timing for first-year (juvenile) and second-year (subadult) King Eiders Somateria spectabilis in relation to their attendant females. We fitted satellite transmitters...
Getting out of harm's way - evacuation from tsunamis
Jeanne M. Jones, Nathan J. Wood, Leslie C. Gordon
2015, Sound Waves: Coastal science and research news from across the USGS (2015)
Scientists at the U.S. Geological Survey (USGS) have developed a new mapping tool, the Pedestrian Evacuation Analyst, for use by researchers and emergency managers to estimate how long it would take for someone to travel on foot out of a tsunami-hazard zone. The ArcGIS software extension, released in September 2014,...
Characterizing toxicity of metal-contaminated sediments from mining areas
John M. Besser, William G. Brumbaugh, Christopher G. Ingersoll
2015, Applied Geochemistry (57) 73-84
This paper reviews methods for testing the toxicity of metals associated with freshwater sediments, linking toxic effects with metal exposure and bioavailability, and developing sediment quality guidelines. The most broadly applicable approach for characterizing metal toxicity is whole-sediment toxicity testing, which attempts to simulate natural exposure conditions in the laboratory....
Correspondence of biological condition models of California streams at statewide and regional scales
Jason T. May, Larry R. Brown, Andrew C. Rehn, Ian R. Waite, Peter R Ode, Raphael D Mazor, Kenneth C Schiff
2015, Environmental Monitoring and Assessment (187)
We used boosted regression trees (BRT) to model stream biological condition as measured by benthic macroinvertebrate taxonomic completeness, the ratio of observed to expected (O/E) taxa. Models were developed with and without exclusion of rare taxa at a site. BRT models are robust, requiring few assumptions compared with traditional modeling...
Spatial patterns of atmospheric deposition of nitrogen and sulfur using ion-exchange resin collectors in Rocky Mountain National Park, USA
David W. Clow, Heidi Roop, Leora Nanus, Mark Fenn, Graham A. Sexstone
2015, Atmospheric Environment (101) 149-157
Lakes and streams in Class 1 wilderness areas in the western United States (U.S.) are at risk from atmospheric deposition of nitrogen (N) and sulfur (S), and protection of these resources is mandated under the Federal Clean Air Act and amendments. Assessment of critical loads, which are the maximum exposure...
Uranium in the Islamic Republic of Mauritania (phase V, deliverable 81)
Gregory Fernette
2015, Open-File Report 2013-1280-N
Mauritania has 80 known uranium mineral occurrences and is the current focus of active exploration for uranium by a number of private companies. Seventeen occurrences have had resource estimates published and can be considered as mineral deposits. Fourteen of these are calcrete-type deposits with a total resource of 138.3 million...
Crystalline basement map of Mauritania derived from filtered aeromagnetic data (deliverable 54_1), Aeromagnetic and geological structure map of Mauritania (phase V, deliverable 54_2), Maximum depth to basement map of Mauritania derived from Euler analysis of Aeromagnetic data (phase V, deliverable 54_3), and color composite image of radioelement data (added value)
Carol A. Finn, John D. Horton
2015, Open-File Report 2013-1280-B1
In 1996, at the request of the Government of the Islamic Republic of Mauritania, a team of U.S. Geological Survey (USGS) scientists produced a strategic plan for the acquisition, improvement and modernization of multidisciplinary sets of data to support the growth of the Mauritanian minerals sector and to highlight the...
Iron oxide copper-gold deposits in the Islamic Republic of Mauritania (phase V, deliverable 79)
Gregory Fernette
2015, Open-File Report 2013-1280-M
Mauritania hosts one significant copper-gold deposit, Guelb Moghrein and several occurrences, which have been categorized as iron oxide copper-gold (IOCG) deposits but which are atypical in some important respects. Nonetheless, Guelb Moghrein is an economically significant mineral deposit and an attractive exploration target. The deposit is of Archean age and...
Accounting for imperfect detection in Hill numbers for biodiversity studies
Kristin M. Broms, Mevin Hooten, Ryan M. Fitzpatrick
2015, Methods in Ecology and Evolution (6) 99-108
Hill numbers unify biodiversity metrics by combining several into one expression. For example, species richness, Shannon's diversity index and the Gini–Simpson index are a few of the most used diversity measures, and they can be expressed as Hill numbers. Traditionally, Hill numbers have been calculated from relative...
Restricted spatial regression in practice: Geostatistical models, confounding, and robustness under model misspecification
Ephraim M. Hanks, Erin M. Schliep, Mevin Hooten, Jennifer A. Hoeting
2015, Environmetrics (26) 243-254
In spatial generalized linear mixed models (SGLMMs), covariates that are spatially smooth are often collinear with spatially smooth random effects. This phenomenon is known as spatial confounding and has been studied primarily in the case where the spatial support of the process being studied is discrete (e.g., areal spatial data)....
Geographic Information Systems (GIS) for la République Islamique de Mauritanie (PRISM-II) phase V (phase V, deliverable 92)
John D. Horton, Cliff D. Taylor
2015, Open-File Report 2013-1280-T
In 1996, at the request of the Government of the Islamic Republic of Mauritania, a team of U.S. Geological Survey (USGS) scientists produced a strategic plan for the acquisition, improvement and modernization of multidisciplinary sets of data to support the growth of the Mauritanian minerals sector and to highlight the...
Mineral potential for nickel, copper, platinum group elements(PGE), and chromium deposits hosted in ultramafic rocks in the Islamic Republic of Mauritania (phase V, deliverable 67)
Cliff D. Taylor, Erin E. Marsh, Eric D. Anderson
2015, Open-File Report 2013-1280-G
PRISM-I summary documents mention the presence of mafic-ultramafic igneous intrusive rocks in several areas of Mauritania and a number of chromium (Cr) and copper-nickel (Cu-Ni (±Co, Au)) occurrences associated with them. Permissive geologic settings generally include greenstone belts of any age, layered mafic-ultramafic and unlayered gabbro-anorthosite intrusive complexes in cratonic...
Mineral potential tracts for orogenic, Carlin-like, and epithermal gold deposits in the Islamic Republic of Mauritania, (phase V, deliverable 69)
Richard J. Goldfarb, Erin E. Marsh, Eric D. Anderson, John D. Horton, Carol A. Finn, Georges Beaudoin
2015, Open-File Report 2013-1280-H
The gold resources of Mauritania presently include two important deposits and a series of poorly studied prospects. The Tasiast belt of deposits, which came into production in 2007, is located in the southwestern corner of the Rgueïbat Shield and defines a world-class Paleoproterozoic(?) orogenic gold ore system. The producing Guelb...
Estimating switchgrass productivity in the Great Plains using satellite vegetation index and site environmental variables
Yingxin Gu, Bruce K. Wylie, Daniel M. Howard
2015, Ecological Indicators (48) 472-476
Switchgrass is being evaluated as a potential feedstock source for cellulosic biofuels and is being cultivated in several regions of the United States. The recent availability of switchgrass land cover maps derived from the National Agricultural Statistics Service cropland data layer for the conterminous United States provides an opportunity to...
Mineral potential for incompatible element deposits hosted in pegmatites, alkaline rocks, and carbonatites in the Islamic Republic of Mauritania (phase V, deliverable 87)
Cliff D. Taylor, Stuart A. Giles
2015, Open-File Report 2013-1280-Q
Review of PRISM-I documents and the National inventory of mineral occurrences suggests that resources of U, Th, Nb, Ta, Be, rare earth elements (REEs) and fluorite are known in Mauritania and have been exploited in the past at the Bou Naga alkaline complex. Several different deposit types are indicated by...
Shoreface response and recovery to Hurricane Sandy: Fire Island, NY
Timothy R. Nelson, Cheryl J. Hapke
Ping Wang, Julie D. Rosati, Jun Cheng, editor(s)
2015, Conference Paper, The proceedings of the coastal sediments 2015
The shoreface of Fire Island was extensively modified by Hurricane Sandy and subsequent storms in the following winter months. The changes were evaluated using various morphometrics of the shoreface from four bathymetric surveys, one prior to Hurricane Sandy, and three over the course of twenty months following Sandy. The datasets...
Database of mineral deposits in the Islamic Republic of Mauritania (phase V, deliverables 90 and 91)
Erin E. Marsh, Eric D. Anderson
2015, Open-File Report 2013-1280-S
Three ore deposits databases from previous studies were evaluated and combined with new known mineral occurrences into one database, which can now be used to manage information about the known mineral occurrences of Mauritania. The Microsoft Access 2010 database opens with the list of tables and forms held within the...
Eocene and Miocene extension, meteoric fluid infiltration, and core complex formation in the Great Basin (Raft River Mountains, Utah)
Katharina Methner, Andreas Mulch, Christian Teyssier, Michael L. Wells, Michael A. Cosca, Raphael Gottardi, Aude Gebelin, C. Page Chamberlain
2015, Tectonics (34) 680-693
Metamorphic core complexes (MCCs) in the North American Cordillera reflect the effects of lithospheric extension and contribute to crustal adjustments both during and after a protracted subduction history along the Pacific plate margin. While the Miocene-to-recent history of most MCCs in the Great Basin, including the Raft River-Albion-Grouse Creek MCC,...
