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Predicting the morphological impacts and associated hazards of extreme storms on barrier islands is facilitated by examining historical poststorm images and identifying the predominant alongshore and cross-shore patterns of erosion and deposition for different island segments. Morphological changes on the Mississippi–Alabama barrier-island chain produced by...

The U.S. Geological Survey (USGS), in cooperation with the San Antonio River Authority, the Evergreen Underground Water Conservation District, and the Goliad County Groundwater Conservation District, configured, calibrated, and tested a watershed model for a study area consisting of about 2,150 square miles of the lower San Antonio River watershed...

In 2006 and 2007, we surveyed the occurrence of bull trout (Salvelinus confluentus), the relative distributions of bull trout and redband trout (Oncorhynchus mykiss), and stream habitat conditions in the East and West Forks of the Jarbidge River in northeastern Nevada and southern Idaho. We installed passive integrated transponder (PIT)...

The U.S. Geological Survey, in cooperation with the U.S. Army Corps of Engineers, compiled salinity-related water-quality data and information in a geodatabase containing more than 6,000 sampling sites. The geodatabase was designed as a tool for water-resource management and includes readily available digital data sources from the U.S. Geological Survey,...

Laguna Grande is a 50-hectare lagoon in the municipio of Fajardo, located in the northeasternmost part of Puerto Rico. Hydrologic, water-quality, and biological data were collected in the lagoon between March 2007 and February 2009 to establish baseline conditions and determine the health of Laguna Grande on the basis of...

The neotropical rust fungus Puccinia psidii(P. psidii) was originally described from the host common guava in its native Brazil but has been found since on hosts throughout the myrtle family (Myrtaceae), including a dramatic host jump to nonnative Eucalyptus plantations. Most rust fungi are able to live only on a very narrow range...

The lower Chetco River is a wandering gravel-bed river flanked by abundant and large gravel bars formed of coarse bed-material sediment. Since the early twentieth century, the large gravel bars have been a source of commercial aggregate for which ongoing permitting and aquatic habitat concerns have motivated this assessment of...

These remotely sensed, geographically referenced elevation measurements of lidar-derived bare-earth (BE) and submerged topography datasets were produced collaboratively by the U.S. Geological Survey (USGS), St. Petersburg Coastal and Marine Science Center, St. Petersburg, FL, and the National Aeronautics and Space Administration (NASA), Wallops Flight Facility, VA. This project provides highly detailed...

The Real Time Flood Alert System is a web-based computer program, developed as a data integration tool, and designed to increase the ability of emergency managers to rapidly and accurately predict flooding conditions of streams in Puerto Rico. The system includes software and a relational database to determine the spatial...

We have compiled a global geological map of Ganymede that represents the most recent understanding of the satellite based on Galileo mission results. This contribution builds on important previous accomplishments in the study of Ganymede utilizing Voyager data and incorporates the many new discoveries that were brought about by examination...

To reduce the adverse effects of arsenic on humans, various technologies are used to remove arsenic from groundwater, most relying on As adsorption on Fe-(oxyhydr)oxides and concomitant oxidation of As(III) by dissolved O2. This reaction can be catalyzed by microbial activity or by strongly oxidizing radical species known to form...

Scattered remnants of highly diverse stratigraphic sections of Tertiary lacustrine limestone, andesite flows, and 23.8–18.2 Ma regional ash-flow tuffs on the north flank of the Mormon Mountains record previously unrecognized deformation, which we interpret as pre–17 Ma uplift and possibly weak extension on the north flank of a growing dome....

The northern Colorado River extensional corridor and Lake Mead region are characterized by prominent gravity and magnetic anomalies that provide insight into the geometry of extensional basins, amount of vertical and strike-slip offset on faults that bound these basins, and composition of major basement blocks. Although large-magnitude extension throughout the...

Pronounced lacustrine sedimentation developed in west-central México during the late Miocene, between approximately 11 and 7 Ma. This was in response to tectonic extension associated with the initial emplacement of the late Miocene substrata of the Trans-Mexican Volcanic Belt. Climatic conditions in west-central México during this interval were relatively warm...

Surprise Valley in northeastern California offers an ideal opportunity to examine the structural setting of a developing extensional basin due to its late Miocene to recent activity in isolation from other major normal fault-bound basins. Seismic velocity and potential field modeling help determine the nature of basin fill and identify...

The U.S. Geological Survey (USGS) and the Massachusetts Office of Coastal Zone Management (CZM) have cooperated to map approximately 200 km² of the Massachusetts inner continental shelf between Duxbury and Hull. This report contains geophysical and geological data collected by the USGS on three cruises between 2006 and 2007. These...

Mantle rheology is one of the essential, yet least understood, material properties of our planet, controlling the dynamic processes inside the Earth's mantle and the Earth's response to various forces. With the advent of GRACE satellite gravity, measurements of mass displacements associated with many processes are now...

New three-dimensional (3D) lithologic and stratigraphic models of the Santa Rosa Plain (California, USA) delineate the thickness, extent, and distribution of subsurface geologic units and allow integration of diverse data sets to produce a lithologic, stratigraphic, and structural architecture for the region. This framework can be used to predict pathways...

Zebra and quagga mussels are fresh water invaders that have the potential to cause severe ecological and economic damage. It is estimated that mussels cause $1 billion dollars per year in damages to water infrastructure and industries in the United States (Pimentel et al., 2004). Following their introduction to the...

Individuals in wild populations face risks associated with both intrinsic (i.e. aging) and external (i.e. environmental) sources of mortality. Condition-dependent mortality occurs when there is an interaction between such factors; however, few studies have clearly demonstrated condition-dependent mortality and some have even argued that condition-dependent mortality does not occur in...

No abstract available....

Lichen diversity along the Mississippi River in the Minneapolis-St. Paul urban area was studied in 2008 by sampling 37 localities along the 110-kilometer river basin, resulting in 76 species, which are thought to represent 80% of the complete flora. A significant decrease in lichen diversity toward the urban part of...

In northwestern Arizona, the high-standing, relatively unextended Colorado Plateau abruptly gives way across a system of major west-dipping normal faults to a highly extended part of the Basin and Range province known as the northern Colorado River extensional corridor. The transition from unextended to highly extended upper crust is unusually...

Habitat colonization and abandonment affects the distribution of a species in space and time, ultimately influencing the duration of time habitat is used and the total area of habitat occupied in any given year. Both aspects have important implications to long-term conservation planning. The importance of patch isolation and area...

Exposure to contaminants other than petroleum hydrocarbons could confound interpretation of Exxon Valdez oil spill effects on biota at Prince William Sound, Alaska. Hence, we investigated polychlorinated biphenyls (PCBs) in blood of sea otters and harlequin ducks sampled during 1998. PCB concentrations characterized by lower chlorinated congeners were highest in...