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The Sunnyside porphyry copper system is part of the concealed San Rafael Valley porphyry system located in the Patagonia Mountains of Arizona. The U.S. Geological Survey is conducting a series of multidisciplinary studies as part of the Assessment Techniques for Concealed Mineral Resources project. To help characterize the size, resistivity,...

This report by the U.S. Geological Survey, prepared in cooperation with the Pennsylvania Department of Environmental Protection, Bureau of Mining and Reclamation, evaluates factors affecting the application of specific-capacity tests in six low-yielding water wells in areas of coal mining or quarrying in Pennsylvania. Factors such as pumping rate, duration...

The ideal study of the effects of methylmercury on the reproductive success of a species of bird would be one in which eggs contained mercury concentrations ranging from controls to very heavily contaminated, all at the same site. Such a study cannot be realized at a mercury contaminated area or...

Expanding development and the prolonged drought from 1999 to 2002 drew attention to the quantity and sustainability of the groundwater resources in Warren County, Virginia. The groundwater flow systems of the county are complex and are controlled by the extremely folded and faulted geology that underlies the county. A study...

Local sensitivity analysis provides computationally frugal ways to evaluate models commonly used for resource management, risk assessment, and so on. This includes diagnosing inverse model convergence problems caused by parameter insensitivity and(or) parameter interdependence (correlation), understanding what aspects of the model and data contribute to measures of uncertainty, and identifying...

The Cape Sable peninsula is located on the southwestern tip of the Florida peninsula within Everglades National Park (ENP). Lake Ingraham, the largest lake within Cape Sable, is now connected to the Gulf of Mexico and western Florida Bay by canals built in the early 1920's. Some of these canals...

The sudden appearance of a large cluster of animals with gross abnormalities may signal a significant change in an ecosystem. We describe an unusual concentration of beak deformities that appear to have arisen rapidly within Alaska and now extend southward along the Pacific Coast. In Alaska we have documented 2,160...

Groundwater is protected in most areas as it is a primary source of drinking water. In the United States, 50% of the population relies on groundwater supplies (Reilly et al., 2008). Groundwater sampling in the United States became commonplace in the 20th century as contaminated water resources became apparent and...

This study sought to examine ecological equivalence of created marshes of different ages using traditional structural measures of equivalence, and tested a relatively novel approach using stable isotopes as a measure of functional equivalence. We compared soil properties, vegetation, nekton communities, and δ13C and δ15N isotope values of blue crab...

In 1984 and 1985, the Oklahoma Department of Wildlife Conservation reintroduced North American river otters (Lontra canadensis) from coastal Louisiana into eastern Oklahoma. Those reintroductions and immigration from Arkansas and possibly northeastern Texas allowed river otters to become reestablished in eastern Oklahoma. Our goals were to determine the contemporary distribution...

SWI and SEAWAT are both computer codes designed to model variable-density systems. One of the options in SWI is to model Dupuit interface flow, where freshwater and seawater are separated by an interface. In this paper we compare seawater intrusion model results of SWI to model results of SEAWAT, which...

How gas is stored in shale-gas systems is a critical element in characterizing these potentially prolific, low-porosity/permeability reservoirs. An integrated mineralogic, geochemical, and porosity/permeability study is of the Upper Devonian-Lower Mississippian Woodford Shale, Arbuckle Mountains, southern Oklahoma, at locations previously described through detailed stratigraphic and spectral gamma surveys, was undertaken...

Discharge and salinity were measured along the southwest and the southeast coast of Florida in Everglades National Park (ENP) within several rivers and creeks from 1996 through 2008. Data were collected using hydro-acoustic instruments and continuous water-quality monitors at fixed monitoring stations. Water flowed through ENP within two distinct drainage...

An existing variable‐density groundwater flow and solute transport model, developed for the northern part of Broward County, Florida, was used to predict the effect of sealevel rise on future coastal groundwater resources. Using average annual conditions from 2005, simulations were performed for 100 years into the future using four different...

Groundwater models can be improved by introduction of additional parameter flexibility and simultaneous use of soft-knowledge. However, these sophisticated approaches have high computational requirements. Cloud computing provides unprecedented access to computing power via the Internet to facilitate the use of these techniques. A modeler can create, launch, and terminate “virtual”...

Losses from infectious diseases are an important component of natural mortality among marine fish species, but factors controlling the ecology of these diseases and their potential responses to anthropogenic changes are poorly understood. We used viral hemorrhagic septicemia virus (VHSV) and a laboratory stock of Pacific herring Clupea pallasii to...

Infectious haematopoietic necrosis virus (IHNV) is one of the most important viral pathogens of salmonids. In rainbow trout, IHNV isolates in the M genogroup are highly pathogenic, while U genogroup isolates are significantly less pathogenic. We show here that, at a multiplicity of infection (MOI) of 1, a representative U...

FTIR and Raman spectromicroscopy were used to characterize the composition of Curvularia protuberata hyphae, and to compare a strain isolated from plants inhabiting geothermal soils with a non-geothermal isolate. Thermal IR source images of hyphae have been acquired with a 64 × 64 element focal plane array detector; single point IR spectra have been obtained with synchrotron source light. In...

A monthly snow accumulation and melt model is used with gridded monthly temperature and precipitation data for the Northern Hemisphere to generate time series of March snow-covered area (SCA) for the period 1905 through 2002. The time series of estimated SCA for March is verified by comparison with previously published...

Chronic viral hemorrhagic septicemia virus (VHSV) infections were established in a laboratory stock of Pacific herring Clupea pallasii held in a large-volume tank supplied with pathogen-free seawater at temperatures ranging from 6.8 to 11.6°C. The infections were characterized by viral persistence for extended periods and near-background levels of host mortality....

The Antarctic Drilling Program (ANDRILL) successfully drilled and cored a borehole, AND-1B, beneath the McMurdo Ice Shelf and into a flexural moat basin that surrounds Ross Island. Total drilling depth reached 1285 m below seafloor (mbsf) with 98 percent core recovery for the detailed study of glacier dynamics. With the...

A common clinical sign of ichthyophoniasis in herring and trout is “sandpaper” skin, a roughening of the epidermis characterized by the appearance of small papules, followed by ulceration and sloughing of the epithelium; early investigators hypothesized that these ulcers might be a means of transmitting the parasite, Ichthyophonus sp., without...

Transportation planners are increasingly incorporating roadway design features to mitigate impacts of highways on wildlife and to increase driver safety. We used camera and track surveys to evaluate wildlife use before and after construction of 3 wildlife underpasses and associated fencing on a new section of United States Highway 64...