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The West African Coastal Province along the west African coastline recently was assessed for undiscovered, technically recoverable oil, natural gas, and natural gas liquids resources as part of the U.S. Geological Survey's USGS World Oil and Gas Assessment. Using a geology-based assessment methodology, the USGS estimated mean volumes of 3.2...

The Nisqually River Delta is located about 25 km south of the Tacoma Narrows in the southern reach of Puget Sound. Delta evolution is controlled by sedimentation from the Nisqually River and erosion by strong tidal currents that may reach 0.95 m/s in the Nisqually Reach. The Nisqually River flows...

High seismicity levels with accelerating uplift (under the resurgent dome) in Long Valley caldera in the eastern Sierra Nevada from 1989 to 1997, triggered upgrades to dilational strainmeters and other instrumentation installed in the early 1980's following a series of magnitude 6 earthquakes. This included two additional high-resolution borehole strainmeters...

Growing visitor traffic and resource use, as well as natural and anthropogenic land and climatic changes, can place increasing stress on lake ecosystems in Denali National Park and Preserve. Baseline data required to substantiate impact assessment in this sub-arctic region is sparse to non-existent. The U.S. Geological Survey, in cooperation...

On May 25-27, 1980, Long Valley caldera was rocked by four M=6 earthquakes that heralded the onset of a wave of seismic activity within the caldera which has continued through the present. Unrest has taken the form of seismic swarms, uplift of the resurgent dome, and areas of vegetation killed...

Rapid changes in ground tilt and GPS positions on Kīlauea Volcano, Hawai'i, are interpreted as resulting from a shallow, two‐segment dike intrusion into the east rift zone that began at 1217 UTC (0217 HST) on 17 June 2007 and lasted almost 3 days. As a result...

In July 2010, in an effort to reduce future catastrophic natural disaster losses for California, the American Red Cross coordinated and sent a delegation of 20 multidisciplinary experts on earthquake response and recovery to Chile. The primary goal was to understand how the Chilean society and relevant organizations responded to...

Research is needed to determine how seepage-control actions planned by the Comprehensive Everglades Restoration Plan (CERP) will affect recharge, groundwater flow, and discharge within the dual-porosity karstic Biscayne aquifer where it extends eastward from the Everglades to Biscayne Bay. A key issue is whether the plan can be accomplished without...

In Yucca Flat, on the Nevada National Security Site in southern Nevada, the migration of radionuclides from tests located in the alluvial deposits into the Paleozoic carbonate aquifer involves passage through a thick, heterogeneous section of late Tertiary and Quaternary alluvial sediments. An understanding of the lateral and vertical changes...

This report describes results from a groundwater data-collection program completed in 2003-2004 by the U.S. Geological Survey in support of the South Platte Decision Support System and in cooperation with the Colorado Water Conservation Board. Two monitoring wells were installed adjacent to existing water-table monitoring wells. These wells were installed...

The diversity in landscapes at the Earth’s surface is the result, amongst other things, of the balance (or imbalance) between soil production and erosion. While erosion rates are well constrained, it is only recently that we have been able to quantify rates of soil production. Uranium-series isotopes have been useful...

An investigation of vadose zone weathering processes has been undertaken on grussic saprolites developed on Californian granitoids. Preliminary results indicate strong climatic control, through infiltration, on the depth and intensity of weathering. At sites with higher infiltration, the vadose zone is comprehensively altered to grussic saprolite and saprock. Conversely, lower...

Volcanic activity is an excellent hook for engaging college and university students in geoscience classes. An increasing number of Internet-accessible real-time and near–real time volcano monitoring data are now available and constitute an important resource for geoscience education; however, relatively few data sets are comprehensive, and many lack background information...

The USGS has a long and proud tradition of objective, unbiased science in service to the Nation. A reputation for impartiality and excellence is one of our most important assets. To help preserve this vital asset, in 2004 the Executive Leadership Team (ELT) of the USGS was charged by the...

No abstract available....

Models of resource selection are being used increasingly to predict or model the effects of management actions rather than simply quantifying habitat selection. Multilevel, or hierarchical, models are an increasingly popular method to analyze animal resource selection because they impose a relatively weak stochastic constraint to model heterogeneity in habitat...

Five U.S. Geological Survey case studies in real-time stream and lake monitoring are presented. The emphases of the case studies are in-stream biological characteristics, fecal coliform bacteria, atrazine, phosphorus, and taste-and-odor compounds....

Assessing hydrologic effects of developing groundwater supplies in Snake Valley required numerical, groundwater-flow models to estimate the timing and magnitude of capture from streams, springs, wetlands, and phreatophytes. Estimating general water-table decline also required groundwater simulation. The hydraulic conductivity of basin fill and transmissivity of basement-rock distributions in Spring and...

People have tracked phenology for centuries and for the most practical reasons: it helped them know when to hunt and fish, when to plant and harvest crops, and when to navigate waterways. Now phenology is being used as a tool to assess climate change and its effects on both natural...

Red Devil Mine, located in southwestern Alaska near the Village of Red Devil, was the state's largest producer of mercury and operated from 1933 to 1971. Throughout the lifespan of the mine, various generations of mills and retort buildings existed on both sides of Red Devil Creek, and the tailings...

A study of the hydrogeology of the Central Oklahoma aquifer was started in 2008 to provide the Oklahoma Water Resources Board (OWRB) hydrogeologic data and a groundwater flow model that can be used as a tool to help manage the aquifer. The 1973 Oklahoma water law requires the OWRB to...

The purpose of the U.S. Geological Survey (USGS) National Oil and Gas Assessment is to develop geology-based hypotheses regarding the potential for additions to oil and gas reserves in priority areas of the United States, focusing on the distribution, quantity, and availability of oil and natural gas resources. The USGS...

Emerging technologies provide scientists with methods to measure Earth processes in new ways. One of these technologies--ultra-high-resolution, ground-based light detection and ranging (lidar)--is being used by USGS Western Geographic Science Center scientists to characterize the role of wind and fire processes in shaping desert landscapes of the Southwest United States....

Medicine Lake volcano forms a broad, seemingly nondescript highland, as viewed from any angle on the ground. Seen from an airplane, however, treeless lava flows are scattered across the surface of this potentially active volcanic edifice. Lavas of Medicine Lake volcano, which range in composition from basalt through rhyolite, cover...

The U.S. Geological Survey, in cooperation with the South Carolina Department of Health and Environmental Control (SCDHEC), is drilling a deep geologic test well at Hilton Head Island, S.C. The test well is scheduled to run between mid-March and early May 2011. When completed, the well will be about 1,000...