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Comprehensive, data-driven geographic information system analyses utilize publicly available lithologic, geochemical, geophysical, and mineral occurrence datasets to delineate gold resource potential in Alaska. These prospectivity analyses successfully identify areas containing known lode gold occurrences, expand areas of high prospectivity around known occurrences, improve the precision of delineation of areas of...

Accelerating relative sea-level rise (RSLR) is threatening coastal wetlands. However, rising CO2 concentrations may also stimulate carbon sequestration and vertical accretion, counterbalancing RSLR. A coastal wetland dominated by a C3 plant species was exposed to ambient and elevated levels of CO2 in situ from 1987 to 2019 during which time ambient CO2 concentration increased...

Many fish species display inter-population and inter-individual egg size variation. Intra-specific differences in egg size seemingly reflect both energetic experiences of individual spawning fish and long-term population responses to differing ecosystems. Optimal egg size theory implies that selection influences a population’s mean egg size in response to its early-life environment,...

The U.S. Army Corps of Engineers, Jacksonville District, is deepening the St. Johns River channel in Jacksonville, Florida, from 40 to 47 feet along 13 miles of the river channel beginning at the mouth of the river at the Atlantic Ocean, in order to accommodate larger, fully loaded cargo vessels....

Groundwater-quality data collected from 1997 through 2018 from 68 monitoring locations open to the Missouri River alluvial aquifer (hereafter referred to as the “alluvial aquifer”) near the Independence, Missouri, well field were analyzed by the U.S. Geological Survey, in cooperation with the City of Independence, Missouri. This analysis was done...

A cooperative study between the National Park Service (NPS) and the U.S. Geological Survey (USGS) characterized groundwater quality and hydrogeology in parts of Pinnacles National Park. The water-quality investigation assessed the geochemistry of springs, wells, surface water, and precipitation and analyzed geochemistry of rock formations that affect the water chemistry...

The Extending Government Funding and Delivering Emergency Assistance Act (Public Law 117-43) was enacted on September 30, 2021. The U.S. Geological Survey received $26.3 million in supplemental funding to repair and replace facilities and equipment, collect high-resolution elevation data, and complete scientific assessments to support direct recovery and rebuilding decisions...

Producing accurate hindcasts and forecasts with coupled models is challenging due to complex parameterizations that are difficult to ground in observational data. We present a calibration workflow that utilizes a series of machine learning algorithms paired with Windsurf, a coupled beach-dune model (Aeolis, the Coastal Dune Model, and XBeach), to produce hindcasts and forecasts of...

Biogeochemical processes are often spatially discrete (hot spots) and temporally isolated (hot moments) due to variability in controlling factors like hydrologic fluxes, lithological characteristics, bio-geomorphic features, and external forcing. Although these hot spots and hot moments (HSHMs) account for a high percentage of carbon, nitrogen and nutrient cycling within the...

Computational methods to characterize secondary migration in porous media traditionally rely on fluid transport equations with assumptions of time invariance, such as flowpath modeling of buoyancy vectors, statistical percolation algorithms, capillary pressure curves, or a form of Darcy’s Law which presumes instantaneous fluid transport. However, in petroleum systems modeling, the...

Many discoveries of active surface processes on Mars have been made due to the availability of repeat high-resolution images from the High Resolution Imaging Science Experiment (HiRISE) onboard the Mars Reconnaissance Orbiter. HiRISE stereo images are used to make digital terrain models (DTMs) and orthorectified images (orthoimages)....

No abstract available....

Mercury (Hg) contamination has been a persistent concern in the Florida Everglades for over three decades due to elevated atmospheric deposition and the system's propensity for methylation and rapid bioaccumulation. Given declines in atmospheric Hg concentrations in the conterminous United States and efforts to...

Biological soil crusts (biocrusts) cover ~12% of the global land surface. They are formed by an intimate association between soil particles, photoautotrophic and heterotrophic organisms, and they effectively stabilize the soil surface of drylands. Quantitative information on the impact of biocrusts on the global cycling and climate effects of aeolian...

Desert riverscape rehabilitation practitioners must contend with compounding effects of increasing human water demand, persistent drought, non-native species establishment, and climate change, which further stress desert riverine ecosystems such as rivers in the Colorado River basin, United States. Herein, we provide our perspective on the importance of natural flows, large...

Humans have influenced global fire activity for millennia and will continue to do so into the future. Given the long-term interaction between humans and fire, we propose a collaborative research agenda linking archaeology and fire science that emphasizes the socioecological histories and consequences of anthropogenic fire in the development of...

Rural residents of Grant, Iowa, and Lafayette Counties in Wisconsin rely on private wells for their water. Contaminants like nitrate and bacteria from septic systems, fertilizer, and manure can contaminate the groundwater that residents use. Groundwater is vulnerable to contamination where the soil layer is thin and the bedrock is...

Smectite can dramatically reduce the strength of crustal faults and may cause creep on natural faults without great earthquakes; however, the frictional mechanism remains unexplained. Here, our shear experiments reveal systematic increase in shear strength with the increase of the ionic radius of interlayer cations among...

Early detection and rapid response (EDRR) can help mitigate and control invasive species outbreaks early on but its success is dependent on accurate identification of invasive species. We evaluated a novel outbreak in San Diego County, California of the Sonoran Spotted Whiptail (Aspidoscelis sonorae) in order to confirm their...

BackgroundIdentifying animal behaviors, life history states, and movement patterns is a prerequisite for many animal behavior analyses and effective management of wildlife and habitats. Most approaches classify short-term movement patterns with high frequency location or accelerometry data. However, patterns reflecting life history across longer time scales can have...

The Nine-banded Armadillo (Dasypus novemcinctus) is a widespread burrowing species with an expanding geographic range across the southeastern and midwestern United States. Armadillos dig numerous, large burrows within their home ranges and these burrows are likely used by a diverse suite of wildlife species as has been reported for other...

The Big Hole River basin in southwestern Montana supports the only indigenous, self‐sustaining fluvial population of Arctic Grayling Thymallus arcticus in the conterminous United States, but the basin is fragmented by numerous low‐head irrigation diversion dams. Denil fishways at 63 diversion dams provide Arctic Grayling and other fishes opportunities for year‐round access...

Credit is the currency of science. Scientists are evaluated and promoted in their jobs and professional communities on the basis of their recognized contributions to science. Unlike a financial contribution, a scientific contribution is difficult to measure. Traditionally, credit for scientific contributions has been given through authorship and citations in...

The study area consists of four contiguous 7.5-minute quadrangles and is located in Frederick and Clarke Counties, Virginia, and Berkeley and Jefferson Counties, West Virginia. The individual quadrangles are Stephenson, Winchester, Inwood, and White Hall. The study area lies within the Great Valley subprovince of the Valley and Ridge physiographic...

To examine controls on the local stress field at Augustine Volcano, Alaska, before its 2006 eruption, we calculated fault plane solutions for volcano-tectonic earthquakes from 2002 to 2006. The P-axis orientation was first aligned to the regional maximum compression (NW) and then rotated by about 90° (perpendicular to the dike...