Search Results

Building a new model, especially one used for policy purposes, takes considerable time, effort, and resources. In justifying such expenditures, one inevitably spends a lot of time denigrating previous models. For example, in pitching the third Uniform California Earthquake Rupture Forecast (UCERF3) (http://www.WGCEP.org/UCERF3), criticisms of the previous model included...

We've invited Michael R. Rosen, water quality specialist within the USGS Water Science Field Team in Carson City and Elizabeth Gierlowski-Kordesch, professor of geology at Ohio University, to take a look at the intriguing new developments that are emerging in limnogeologic studies. These studies are increasing our understanding of how...

The case study presented here reviews the uranium resource estimates and summarizes the property situation of the Coles Hill uranium Deposit. Uranium resources at Coles Hill are then classified according to UNFC-2009. The Coles Hill Deposit is located in Pittsylvania County, southern Virginia, United States (Figure 14). Coles Hill was...

The late Cenozoic stratigraphic and tectonic history of the Santa Clara Valley illustrates the dynamic nature of the North American–Pacific plate boundary and its effect on basin and landscape development. Prior to early Miocene time, the area that became Santa Clara Valley consisted of eroding Franciscan complex basement structurally interleaved...

This Annual Report summarizes results of grizzly bear (Ursus arctos) monitoring and research conducted in the Greater Yellowstone Ecosystem (GYE) by the Interagency Grizzly Bear Study Team (IGBST) during 2014. The report also contains a summary of grizzly bear management actions to address conflict situations. ...

No abstract available....

We extend the approach underlying the well-known Dix equation in reflection seismology to surface waves. Within the context of surface wave inversion, the Dix-type relation we derive for surface waves allows accurate depth profiles of shear-wave velocity to be constructed directly from phase velocity data, in contrast to perturbational methods....

The demand for ecosystem services and the ability of natural ecosystems to provide those services evolve over time as population, land use, and management practices change. Regionalization of ecosystem service activity, or the expansion of the area providing ecosystem services to a population, is a common response in densely populated...

Some of the most compelling examples of ecological responses to climate change are elevational range shifts of individual species, which have been observed throughout the world. A growing body of evidence, however, suggests substantial mediation of simple range shifts due to climate change by other limiting factors. Understanding limiting factors...

Soluble reactive phosphorus (SRP) concentrations have been stable in nearshore and offshore habitats since 1998 (0.4 – 3.3 μg/L). SRP concentrations were low in 2014; Apr/May – Oct mean values were <1 μg/L at most sites. Spring TP concentrations at individual sites exceeded 10 μg/L on occasion, but spring means...

Identifying the scale of dispersal among habitats has been a challenge in marine ecology for decades (Grantham et al., 2003; Kinlan & Gaines, 2003; Hixon, 2011). Unlike terrestrial habitats in which barriers to dispersal may be obvious (e.g. mountain ranges, rivers), few absolute barriers to dispersal are recognizable in the...

Lake deposystems are commonly associated with retroarc mountain belts in the geological record. These deposystems are poorly characterized in modern retroarcs, placing limits on our ability to interpret environmental signals from ancient deposits. To address this problem, we have synthesized our existing knowledge about the distribution, morphometrics, and sedimentary geochemical...

SO2 camera measurements at Kīlauea Volcano, Hawaii, in May of 2010 captured two occurrences of lava lake rise and fall within the Halema'um'au Crater summit vent. During high lava stands we observed diminished SO2 emission rates and decreased seismic tremor. Similar events at Kīlauea have been described as the result...

Linked atmospheric and wildfire changes will complicate future management of native coldwater fishes in fire-prone landscapes, and new approaches to management that incorporate uncertainty are needed to address this challenge. We used a Bayesian network (BN) approach to evaluate population vulnerability of...

Trench and wetland coring studies show that northeast‐striking strands of the Saddle Mountain fault zone ruptured the ground about 1000 years ago, generating prominent scarps. Three conspicuous subparallel fault scarps can be traced for 15 km on Light Detection and Ranging (LiDAR) imagery, traversing the foothills of the southeast Olympic Mountains:...

Rapid urbanization has resulted in a series of sequential effects on a desert stream in the American Southwest. Lower Las Vegas Wash was a dry wash characterized by infrequent flood deposition when Las Vegas, Nevada was established in 1905. Wastewater effluent was discharged into the wash in low volumes for...

Under the World Bank-funded Second Projet de Renforcement Institutionnel du Secteur Minier de la Republique Islamique de Mauritanie (PRISM-II), this Phase V geochemistry report follows earlier Phase I and Phase II summary reports on geochemical data (U.S. Geological Survey, 2007 and Eppinger, 2007; respectively). All the reports are based on...

High-resolution multibeam bathymetry data collected with an autonomous underwater vehicle (AUV) complemented by compressed high-intensity radar pulse (Chirp) profiles and remotely operated vehicle (ROV) observations and sediment sampling reveal a distinctive rough topography associated with seafloor gas venting and/or near-subsurface gas hydrate accumulations. The surveys provide 1 m bathymetric grids...

State-and-transition simulation models (STSMs) are known for their ability to explore the combined effects of multiple disturbances, ecological dynamics, and management actions on vegetation. However, integrating the additional impacts of climate change into STSMs remains a challenge. We address this challenge by combining an STSM with species distribution modeling (SDM)....

The composite Sunrise Butte pluton, in the central part of the Blue Mountains Province, northeastern Oregon, preserves a record of subduction-related magmatism, arc-arc collision, crustal thickening, and deep-crustal anatexis. The earliest phase of the pluton (Desolation Creek unit) was generated in a subduction zone environment, as the oceanic lithosphere between the...

Effects of hydrology on growth and hatching success of age-0 black basses and Channel Catfish were examined in regulated and unregulated reaches of the Tallapoosa River, Alabama. Species of the family Centrarchidae, Ictalurus punctatus Channel Catfish and Pylodictis olivaris Flathead Catfish were also collected from multiple tributaries in the basin....

Although many Archaea have AMP-Acs (acetyl-coenzyme A synthetase) and ADP-Acs, the extant methanogenic genus Methanosarcina is the only identified Archaeal genus that can utilize acetate via acetate kinase (Ack) and phosphotransacetylase (Pta). Despite the importance of ack as the potential urkinase in the ASKHA phosphotransferase superfamily, an origin hypothesis does...

The epicenters of the main shock and associated aftershocks of the 2011 moment magnitude, Mw 5.8 Mineral, Virginia (USA), earthquake, and the updip projection of the possible fault plane that triggered the quakes, are contained in the areas of 2 adjoining 7.5′ quadrangles in the central Virginia Piedmont. These quadrangles...

No abstract available....

Increased land-use intensity (e.g. clearing of forests for cultivation, urbanization), often results in the loss of ecosystem carbon storage, while changes in productivity resulting from climate change may either help offset or exacerbate losses. However, there are large uncertainties in how land and climate systems will evolve and interact to...