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We mapped a poorly documented 35-km-long section of the northern San Andreas fault zone (NSAF) between Tomales Point and Fort Ross, California. Mapping is largely based on high-resolution seismic-reflection profiles (38 fault crossings), multibeam bathymetry, and onshore geology. NSAF strike in this section is nearly parallel to plate motion, characterized...

Investigations into the effects of riparian shade on water quality have focused on streams, with less emphasis on natural lakes, and almost no attention given to reservoirs. In view of this gap, our objective was to assess diel water quality patterns in the nearshore zone of a reservoir and test...

A binational study was initiated to update statistical equations that are used to estimate the magnitude and frequency of peak flows on streams in Manitoba and Ontario, Canada, and Minnesota that are contained within the binational Lake of the Woods–Rainy River Basin upstream from Kenora, Ontario, Canada. Hydraulic engineers use...

The Cedar River alluvial aquifer is the primary source of municipal water in Cedar Rapids, Iowa. Municipal wells are completed in the alluvial aquifer about 40 to 80 feet below land surface. The City of Cedar Rapids and the U.S. Geological Survey have led a cooperative study of the groundwater-flow...

The dynamic, multiscale nature of stream systems makes it challenging to establish basic ecological principles to guide stream fish conservation and management. For example, finer-scale instream habitat is often constrained by coarser-scale characteristics driving observed species distributions. Additionally, instream environmental variability can result in patchy species distributions within general upstream–downstream...

This is a chapter in a technical report that is the second of two works describing longer-term actions to implement policies and strategies for preventing and suppressing rangeland fire and restoring rangeland landscapes affected by fire in the Western United States. The first part, Chambers et al 2017, "Science...

Aluminum precipitates control the hydrochemistry and mineralogy of a broad variety of environments on Earth (e.g., acid mine drainage, AMD, coastal wetlands, boreal and alpine streams, tropical acid sulfate soils, laterites and bauxites, …). However, the geochemical and mineralogical processes controlling Al (and other associated metals and metalloids) transport and removal in those environments...

Spatial redistribution of legacy mercury (Hg) contamination in the Hackensack River estuary (New Jersey, USA) was evaluated using mercury stable isotopes. Total Hg varied from 0.06 to 3.8 µg g-1 in sediment from the tidal Hackensack River and from 15 to 154 µg g-1 near historically contaminated sites in...

The quantity and character of dissolved organic matter (DOM) can change rapidly during storm events, affecting key biogeochemical processes, carbon bioavailability, metal pollutant transport, and disinfection byproduct formation during drinking water treatment. We used in situ ultraviolet–visible spectrophotometers to concurrently measure dissolved organic carbon (DOC) concentration...

Land degradation is a persistent ecological problem in many arid and semi-arid systems globally (drylands hereafter). Most instances of dryland degradation include some form of soil disturbance and/or soil erosion, which can hinder vegetation establishment and reduce ecosystem productivity. To combat soil erosion, researchers have identified a need...

Paleohydrologic reconstructions of water-year streamflow for 105 sites across the western United States (West) were used to compute the likelihood (risk) of regime (wet/dry state) shifts given the length of time in a specific regime and for a specified time in the future. The spatial variability...

The Arctic Alaska basin occupies the eastern part of the Arctic Alaska – Chukotka microplate, which rifted from the Canadian Arctic margin during opening of the Canada Basin. Stratigraphy comprises four tectonostratigraphic sequences. (1) The Devonian and older Franklinian sequence consists of sedimentary and metasedimentary rocks deposited on the Arctic...

The traditional flow of coastal ocean model data is from High Performance Computing (HPC) centers to the local desktop, or to a file server where just the data needed can be extracted via services such as OPeNDAP. Analysis and visualization is then conducted using local hardware and software. This...

Rivermouth ecosystems in the Laurentian Great Lakes represent complex hydrologic mixing zones where lake and river water combine to form biologically productive areas that are functionally similar to marine estuaries. As urban, industrial, shipping, and recreational centers, rivermouths are the focus of human interactions with the Great Lakes and, likewise,...

Executive SummaryThe U.S. Geological Survey, the National Oceanic and Atmospheric Administration, the European Association for Remote Sensing Companies, and the European Space Agency in coordination with the GEOValue Community hosted a side event to the Group on Earth Observations Plenary on October 23–24, 2017, in Washington, D.C. The workshop, entitled...

Organic chemicals from industrial, agricultural, and residential activities can enter surface waters through regulated and unregulated discharges, combined sewer overflows, stormwater runoff, accidental spills, and leaking septic-conveyance systems on a daily basis. The impact of point and nonpoint contaminant sources can result in adverse biological effects for organisms living in...

The tropics are a region encircling the equator, delineated to the north by the Tropic of Cancer (23°26′14.0″N) and to the south by the Tropic of Capricorn (23°26′14.0″S). While we often think of the tropics as consistently warm and wet throughout the year, in reality, the tropics maintain a myriad of...

Multiple-use public lands require balancing diverse resource uses and values across landscapes. In the California desert, there is strong interest in renewable energy development and important conservation concerns. The Bureau of Land Management recently completed a land-use plan for the area that provides protection for modeled suitable habitat for multiple...

Pennsylvania has the second highest number of residential wells of any state in the Nation with approximately 2.4 million residents that depend on groundwater for their domestic water supply. Despite the widespread reliance on groundwater in rural areas of the state, publicly available data to characterize the quality of private...

In this research, we characterized the changes in Gravity Recovery and Climate Experiment’s (GRACE) monthly total water storage anomaly (TWSA) in 18 surface basins and 12 principal aquifers in the Conterminous United States (CONUS) over 2003–2016. Regions with high variability in storage were identified. Ten basins and 4 aquifers showed...

Landsat 9 is a partnership between the National Aeronautics and Space Administration and the U.S. Geological Survey that will continue the Landsat program’s critical role of repeat global observations for monitoring, understanding, and managing Earth’s natural resources. Since 1972, Landsat data have provided a unique resource for those who work...

Historical training and operational activities at Joint Base Cape Cod (JBCC) on western Cape Cod, Massachusetts, have resulted in the release of contaminants into an underlying glacial aquifer that is the sole source of water to the surrounding communities. Remedial systems have been installed to contain and remove contamination from...

Public and domestic water supplies in Elbert County, Colorado, rely on groundwater withdrawals from five bedrock aquifers in the Denver Basin aquifer system (lower Dawson, upper Dawson, Denver, Arapahoe, and Laramie-Fox Hills) to meet water demands. Increased pumping in response to regional population growth and development has led to declining...

Identification of habitats responsible for the successful production and recruitment of rare migratory species is a challenge in conservation biology. Here, a tool was developed to assess life stage linkages for the threatened potamodromous cyprinid Clear Lake hitch Lavinia exilicauda chi. Clear Lake hitch undertake migrations from Clear Lake...

The uplift history of the Colorado Plateau has been debated for over a century with still no unified hypotheses for the cause, timing, and rate of uplift. 40Ar/39Ar and K/Ar dating of recurrent basaltic volcanism over the past ∼6 Ma within the Virgin River drainage system, southwest Utah, northwest Arizona, and...