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IntroductionWater is an important resource in the arid southwest region of the United States where there is a limited supply of surface water and groundwater. In the Death Valley regional groundwater flow system (DVRFS) in southern Nevada and eastern California, groundwater is the main source of supply for agricultural, commercial,...

The volume of available groundwater and the effect of groundwater pumping in an alluvial basin is influenced in part by the shape and depth of the basin boundary, which commonly consists of low-permeability bedrock. To better understand the shape and depth of basin fill in the Truxton valley in Arizona,...

The geology of northwestern Arizona is prominently displayed on the canyon and cliff walls that compose the high-desert landscape of the Hualapai Plateau and that border the Truxton basin. The Truxton basin is a small topographic basin filled with Quaternary and Tertiary deposits and volcanic rock (about 1,600 feet thick...

Terrestrial salamanders are adapted to moist, cool microenvironments that facilitate cutaneous respiration and decrease risk of desiccation. Warmer, drier microenvironments may induce habitat use changes by salamanders to alleviate stressful microenvironmental conditions. Changes in salamander habitat use may bias population metrics when sampling occurs in areas with different microenvironmental conditions....

In an effort to determine whether fish populations in an area affected by wood tar waste exhibited health effects, fish were collected and analyzed with histopathology. Multiple species, including Mottled Sculpin (Cottus bairdii), Creek Chub (Semotilus atromaculatus), White Sucker (Catostumus commersonii), Redside Dace (Clinostomus elongatus), Common Shiner (Luxilus cornutus), and...

In recent years, geologists and petroleum engineers have struggled to clearly identify the mechanisms that drive productivity in horizontal, hydraulically-fractured oil wells producing from the middle member of the Bakken formation. This paper fills a gap in the literature by showing how this play’s heterogeneity affects factors that drive well...

Recent work on cores and outcrops of the Middle-Upper Triassic Shublik Formation has facilitated surface to subsurface correlation of depositional sequences across the Alaska North Slope. Five transgressive-regressive depositional sequences have been defined within three large-scale stratigraphic units. Outcrop spectral gamma-ray (GR) profiles were used to correlate observed stacking patterns...

ObjectiveTiger beetles inhabiting sandy beaches and cliffs along the east coast of the United States are facing increasing habitat loss due to erosion, urbanization, and sea level rise. The northeastern beach tiger beetle Cicindela dorsalis dorsalis and Puritan tiger beetle Cicindela puritana are both listed as threatened under the Endangered Species Act of...

The U.S. Geological Survey (USGS) determined the physical and chemical properties of more than 260 feed coal and coal combustion byproducts from two coal-fired power plants. These plants utilized a low-sulfur (0.23-0.47 wt. % S) and low ash (4.9-6.3 wt. % ash) subbituminous coal from the Wyodak-Anderson coal zone...

Boat electrofishing is often used to sample age-0 Muskellunge Esox masquinongy for indexing recruitment or evaluating stocking success. However, electrofishing samples typically result in low CPUE, prompting concerns regarding whether catch rates reflect actual abundance or whether boat electrofishing is generally ineffective for capturing age-0 Muskellunge (i.e., if fish are not being...

This geologic map depicts and briefly describes geologic units underlying Petroglyph National Monument and immediately adjacent areas in Bernalillo County, New Mexico. The Monument is underlain dominantly by Quaternary basalts of the Albuquerque Volcanoes volcanic field, a series of basin-filling volcanic flows and associated vents from a monogenetic volcanic highland...

Crop emergence is a critical stage for crop development and crop growth modeling. Mapping crop emergence using remote sensing data is challenging. Previous remote sensing phenology algorithms showed that crop stages could be detected around the V3-V4 (3 to 4 established leaves) vegetative stage. Traditional approaches have a strong assumption...

Understanding the drivers of vegetation dynamics and no-analog communities in eastern North America is hampered by a scarcity of independent temperature indicators. We present a new branched glycerol dialkyl glycerol tetraether (brGDGT) temperature record from Bonnet Lake, Ohio (18 to 8 ka) and report uncertainty estimates based on Bayesian linear...

Cool and warm season precipitation totals have been reconstructed on a gridded basis for North America using 439 tree-ring chronologies correlated with December-April totals and 547 different chronologies correlated with May-July totals. These discrete seasonal predictor chronologies are not significantly correlated with the alternate season and the reconstructions calibrate...

Alaska represents a globally important region for the ecology of avian-origin influenza A viruses (IAVs) given expansive wetlands in this region which serve as habitat for numerous hosts of IAVs that disperse among four continents during the annual cycle. Extensive sampling of wild birds for IAVs in Alaska since...

Our scientific understanding of the climate system strongly supports the conclusion that North Carolina’s climate has changed in recent decades and the expectation that large changes—much larger than at any time in the state’s history—will occur if current trends in greenhouse gas concentrations continue. Even under a scenario where emissions...

The organic composition of produced waters (flowback and formation waters) from the middle member of the Bakken Formation and the Three Forks Formation in the Williston Basin, North Dakota were examined to aid in the remediation of surface contamination and help develop treatment methods for produced-water recycling. Twelve produced water...

The U.S. Pacific Northwest has a history of frequent and occasionally deadly landslides caused by various factors. Using a multivariate, machine-learning approach, we combined a Pacific Northwest Landslide Inventory with a 36-year gridded hydrologic dataset from the National Climate Assessment – Land Data Assimilation System to produce a landslide hazard indicator (LHI) on a...

Groundwater flow and development were characterized in four groundwater basins of the Death Valley regional flow system in Nevada and California with calibrated, groundwater-flow models. Natural groundwater discharges in the Furnace Creek, Lower Amargosa, and Saratoga Spring areas were defined and distributed consistently with a revised hydrogeologic...

The harbor structures/shoreline armoring on the southern Lake Michigan shoreline interrupt sand migration. Ogden Dunes, Indiana, and the nearby Indiana Dunes National Lakeshore observed shoreline erosion due to engineered structures associated with Burns Waterway Harbor, east of Ogden Dunes, impeding natural east to west sediment migration. To remedy this, USACE...

Eurasian zebra and quagga mussels were likely introduced to the Laurentian Great Lakes via ballast water release in the 1980s, and their range has since expanded across the US, including some of their southernmost occurrences in Texas. Their spread into the state has resulted in a need to revise previous...

The Snake River volcanic province (SRP) has long been considered a target for geothermal development. It overlies a thermal anomaly that extends deep into the mantle and represents one of the highest heat flow provinces in North America, but systematic exploration been hindered by lack of a conceptual model. Play...

The Trout Rock caves (Hamilton Cave, Trout Cave, New Trout Cave) are located in a hill named Cave Knob that overlooks the South Branch of the Potomac River in Pendleton County, West Virginia (U.S.A). The geologic structure of this hill is a northeasttrending anticline, and the caves are located at...

The behavior of wildlife varies seasonally, and that variation can have substantial demographic consequences. This is especially true for long‐distance migrants where the use of landscapes varies by season and, sometimes, age cohort. We tested the hypothesis that distributional patterns of Golden Eagles (Aquila chrysaetos) wintering...

The U.S. Geological Survey’s National Water-Quality Assessment (NAWQA) Project assessed the quality of groundwater in aquifers that are important sources of drinking water in the United States. One major aquifer in Texas that was assessed by NAWQA in 2013 is the coastal lowlands aquifer system, which is often referred to...