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Western Mineral and Environmental Resources Science Center--providing comprehensive earth science for complex societal issues

Minerals in the environment and products manufactured from mineral materials are all around us and we use and come into contact with them every day. They impact our way of life and the health of all that lives. Minerals are critical to the Nation's economy and knowing where future mineral resources will come from is important for sustaining the Nation's economy and national security. The U.S. Geological Survey (USGS) Mineral Resources Program (MRP) provides scientific information for objective resource assessments and unbiased research results on mineral resource potential, production and consumption statistics, as well as environmental consequences of mining. The MRP conducts this research to provide information needed for land planners and decisionmakers about where mineral commodities are known and suspected in the earth's crust and about the environmental consequences of extracting those commodities. As part of the MRP scientists of the Western Mineral and Environmental Resources Science Center (WMERSC or 'Center' herein) coordinate the development of national, geologic, geochemical, geophysical, and mineral-resource databases and the migration of existing databases to standard models and formats that are available to both internal and external users. The unique expertise developed by Center scientists over many decades in response to mineral-resource-related issues is now in great demand to support applications such as public health research and remediation of environmental hazards that result from mining and mining-related activities. Western Mineral and Environmental Resources Science Center Results of WMERSC research provide timely and unbiased analyses of minerals and inorganic materials to (1) improve stewardship of public lands and resources; (2) support national and international economic and security policies; (3) sustain prosperity and improve our quality of life; and (4) protect and improve public health, safety, and environmental quality. The MRP supports approximately 40 USGS research specialists who utilize cooperative agreements with universities, industry, and other governmental agencies to support their collaborative research and information exchange. Scientists of the WMERSC study how and where non-fuel mineral resources form and are concentrated in the earth's crust, where mineral resources might be found in the future, and how mineral materials interact with the environment to affect human and ecosystem health. Natural systems (ecosystems) are complex - our understanding of how ecosystems operate requires collecting and synthesizing large amounts of geologic, geochemical, biologic, hydrologic, and meteorological information. Scientists in the Center strive to understand the interplay of various processes and how they affect the structure, composition, and health of ecosystems. Such understanding, which is then summarized in publicly available reports, is used to address and solve a wide variety of issues that are important to society and the economy. WMERSC scientists have extensive national and international experience in these scientific specialties and capabilities - they have collaborated with many Federal, State, and local agencies; with various private sector organizations; as well as with foreign countries and organizations. Nearly every scientific and societal challenge requires a different combination of scientific skills and capabilities. With their breadth of scientific specialties and capabilities, the scientists of the WMERSC can provide scientifically sound approaches to a wide range of societal challenges and issues. The following sections describe examples of important issues that have been addressed by scientists in the Center, the methods employed, and the relevant conclusions. New directions are inevitable as societal needs change over time. Scientists of the WMERSC have a diverse set of skills and capabilities and are proficient in the collection and integration of

Circular

Magnitude and frequency of floods for rural streams in Georgia, South Carolina, and North Carolina, 2017—Summary

Reliable flood-frequency estimates are important for hydraulic structure design and floodplain management in Georgia, South Carolina, and North Carolina. Annual peak streamflows (hereafter, referred to as peak flows) measured at 965 U.S. Geological Survey streamgages were used to compute flood-frequency estimates with annual exceedance probabilities (AEPs) of 50, 20, 10, 4, 2, 1, 0.5, and 0.2 percent. These AEPs correspond to flood-recurrence intervals of 2, 5, 10, 25, 50, 100, 200, and 500 years, respectively. A subset of these streamgages (801) were used to develop equations to predict the AEP flood flows at ungaged stream locations. This study was completed by the USGS in cooperation with the Georgia, South Carolina, and North Carolina Departments of Transportation and the North Carolina Department of Crime Control and Public Safety, and the results are summarized in this fact sheet. The complete results and the supporting data are presented in the companion scientific investigations report and data release.

Georgia, North Carolina, South Carolina

Design and implementation of a structural health monitoring and alerting system for hospital buildings in the United States

This paper describes the current progress in the development of a structural health monitoring and alerting system to meet the needs of the U.S. Department of Veterans Affairs to monitor hospital buildings instrumented in high and very high seismic hazard regions in the U.S. The system, using the measured vibration data, is primarily designed for post-earthquake condition assessment of the buildings. It has two essential components – sensing and analysis. The sensing component includes all necessary firmware and sensors to measure the response of the building; while the analysis component consists of several data processing modules integrated into an open source software package which compresses a large amount of measured data into useful information to assess the building’s condition before and after an event. The information can be used for a rapid building safety assessment, and to support decisions for necessary repairs, replacements, and other maintenance and rehabilitation measures.

Conference Paper

Using structure from motion photogrammetry to examine glide snow avalanches

Structure from Motion (SfM), a photogrammetric technique, has been used extensively and successfully in many fields including geosciences over the past few years to create 3D models and high resolution digital elevation models (DEMs) from aerial or oblique photographs. SfM has recently been used in a limited capacity in snow avalanche research and shows promise as a tool for broader applications. In this study, we used SfM to examine glide avalanches along the Going-to-the-Sun Road (GTSR) corridor in Glacier National Park (GNP), Montana. Glide avalanches pose substantial hazard to railroads, highways, and other infrastructure in many avalanche prone regions around the world, and yet basic measurements of crown depth and ground/snow interface can be hard to observe. Along the GTSR, glide avalanches can impact worker and public safety, but accessing glide avalanche crowns or glide cracks is often prohibited by inaccessible terrain or residual avalanche hazard. We used SfM techniques to derive high resolution DEMs for four glide avalanches that occurred in the spring of 2016. This allowed us to estimate selected full depth glide avalanche dimensions without visiting the site. However, our analysis was limited to qualitative assessments of the glide avalanche dimensions as the high resolution coordinates necessary to analyze the vertical dimension of avalanche crowns were not available. Despite this, our results suggest SfM can be a robust tool for examining glide avalanche crowns and of sufficient resolution to accurately characterize glide avalanche dimensions. Under a warming and more variable future climate, glide avalanches could become a more prevalent problem, and using SfM as a tool to help characterize glide avalanches over a larger spatial area will help us to better document and further understand these phenomena.

Conference Paper

Spatio-temporal modeling for assessing geoenergy resources: A workflow applied to gas in place variation in coal beds

The ability to estimate spatio-temporal changes in hydrocarbon reservoir properties and energy resources within pore volumes is essential for optimizing production, reservoir management, geologic energy storage, and safety in underground mining operations. In coal seams, predicting remaining methane gas-in-place (GIP) is critical for quantifying producible gas and improving mine safety and productivity through effective ventilation planning. Although such changes are commonly evaluated using physics-based numerical simulation models, these approaches often require extensive data, calibration effort, and time. This study presents a spatio-temporal geostatistical modeling approach that bridges the gap between purely spatial models and full numerical simulations. The method is applied to a case study of coal seam degasification in the Mary Lee coal group, Black Warrior Basin, Alabama, USA, to estimate GIP evolution over time within a selected mining district. The analysis uses published data from prior natural gas production history-matching of degasification using vertical wells. Empirical spatial and temporal statistics were calculated for reservoir pressure and water saturation, and spatio-temporal variogram models were fitted to experimental variograms. These models provided the structural basis for spatio-temporal kriging, integrated with spatial estimates of time-invariant parameters (porosity, density, and thickness) to estimate GIP. This approach enabled estimation of GIP changes over time, including periods without data. Boxplots of GIP estimates indicated systematic depletion and decreasing spatial variability, reflecting the impacts of degasification. Comparison with cumulative gas production from empirical well records showed approximately 85% agreement based on a relative similarity metric. Spatio-temporal GIP estimates were also used to estimate methane emissions to longwall ventilation systems and compared with reported emissions from the U.S. EPA Greenhouse Gas Reporting Program, showing similar distributions (≈80%) given data limitations. Overall, this integrated modeling approach provides time-dependent GIP estimates with broader implications for resource assessment applications.

Alabama

Investigation of bridge scour at selected sites on Missouri streams

Scour around bridge piers is a major concern in the design of a new bridge or the evaluation of the structural stability of an existing bridge. An adequate estimation of potential scour at bridge piers is essential to effective design, construction, and maintenance of hydraulic structures. Reasonably accurate estimates of scour depth are needed for safe, cost-effective bridge design. Although many equations have been developed on the basis of laboratory work that can be used to estimate local scour at piers, site-specific data have not previously been collected to verify the accuracy of these equations or applicability to Missouri streams. Scour data were collected during floods at 10 sites on streams in Missouri. The recurrence intervals of the floods ranged from less than 2 to more than 50 years. Local-scour holes near bridge piers ranged from 0.5 to 7.1 feet deep. Seven local-pier-scour equations were evaluated as to their usefulness in estimating the measured scour at the sites studied. Scour depths estimated using the Froehlich equatin without a safety factor had an interquartile range nearest in magnitude to the interquartile range of the measured scour depths. None of the medians of scour depths estimated using the seven equations were statistically equal to the median of the measured scour depths at a 0.05 level of significance. However, the Froehlich equation without a safety factor provided the "best fit" estimates of the equations considered. Contraction scour exceeded local scour by several times in some cases. Total scour of approximately 19 feet, largely becasue of contraction scour, was measured at the Chariton River near Prairie Hill during the flood of July 8, 1993. This large scour was, in part, the result of an accumulation of woody debris de- creasing the bridge-opening area. A bridge on State Highway 32 near Lebanon over North Cobb Creek (drainage area 52.5 square miles) was destroyed during the flood of May 26, 1990. Bridge scour attributable to contraction of the flood flow caused this loss.

Missouri

The National Map - Washington-Idaho Pilot Project

Governments depend on a common set of geographic base information as a tool for economic and community development, land and natural resource management, and health and safety services. Emergency management and defense operations rely on this information. Private industry, nongovernmental organizations, and individual citizens use the same geographic data. Geographic information underpins an increasingly large part of the Nation's economy. Available geographic data often have the following problems: * They do not align with each other because layers are frequently created or revised separately, * They do not match across administrative boundaries because each producing organization uses different methods and standards, and * They are not up to date because of the complexity and cost of revision. The U.S. Geological Survey (USGS) is developing The National Map to be a seamless, continuously maintained, and nationally consistent set of online, public domain, geographic base information to address these issues. The National Map will serve as a foundation for integrating, sharing, and using other data easily and consistently. In collaboration with other government agencies, the private sector, academia, and volunteer groups, the USGS will coordinate, integrate, and, where needed, produce and maintain base geographic data. The National Map will include digital orthorectified imagery; elevation data; vector data for hydrography, transportation, boundary, and structure features; geographic names; and land cover information. The data will be the source of revised paper topographic maps. Many technical and institutional issues must be resolved as The National Map is implemented. To begin the refinement of this new paradigm, pilot projects are being designed to identify and investigate these issues. The pilots are the foundation upon which future partnerships for data sharing and maintenance will be built.

Fact Sheet

The National Map - Missouri Pilot Project

Governments depend on a common set of geographic base information as a tool for economic and community development, land and natural resource management, and health and safety services. Emergency management and defense operations rely on this information. Private industry, nongovernmental organizations, and individual citizens use the same geographic data. Geographic information underpins an increasingly large part of the Nation's economy. Available geographic data often have the following problems: * They do not align with each other because layers are frequently created or revised separately, * They do not match across administrative boundaries because each producing organization uses different methods and standards, and * They are not up to date because of the complexity and cost of revision. The U.S. Geological Survey (USGS) is developing The National Map to be a seamless, continuously maintained, and nationally consistent set of online, public domain, geographic base information to address these issues. The National Map will serve as a foundation for integrating, sharing, and using other data easily and consistently. In collaboration with other government agencies, the private sector, academia, and volunteer groups, the USGS will coordinate, integrate, and, where needed, produce and maintain base geographic data. The National Map will include digital orthorectified imagery; elevation data; vector data for hydrography, transportation, boundary, and structure features; geographic names; and land cover information. The data will be the source of revised paper topographic maps. Many technical and institutional issues must be resolved as The National Map is implemented. To begin the refinement of this new paradigm, pilot projects are being designed to identify and investigate these issues. The pilots are the foundation upon which future partnerships for data sharing and maintenance will be built.

Fact Sheet

The National Map - Delaware Pilot Project

Governments depend on a common set of geographic base information as a tool for economic and community development, land and natural resource management, and health and safety services. Emergency management and defense operations rely on this information. Private industry, nongovernmental organizations, and individual citizens use the same geographic data. Geographic information underpins an increasingly large part of the Nation's economy. Available geographic data often have the following problems: * They do not align with each other because layers are frequently created or revised separately, * They do not match across administrative boundaries because each producing organization uses different methods and standards, and * They are not up to date because of the complexity and cost of revision. The U.S. Geological Survey (USGS) is developing The National Map to be a seamless, continuously maintained, and nationally consistent set of online, public domain, geographic base information to address these issues. The National Map will serve as a foundation for integrating, sharing, and using other data easily and consistently. In collaboration with other government agencies, the private sector, academia, and volunteer groups, the USGS will coordinate, integrate, and, where needed, produce and maintain base geographic data. The National Map will include digital orthorectified imagery; elevation data; vector data for hydrography, transportation, boundary, and structure features; geographic names; and land cover information. The data will be the source of revised paper topographic maps. Many technical and institutional issues must be resolved as The National Map is implemented. To begin the refinement of this new paradigm, pilot projects are being designed to identify and investigate these issues. The pilots are the foundation upon which future partnerships for data sharing and maintenance will be built.

Fact Sheet

The National Map - Utah Transportation Pilot Project

Governments depend on a common set of geographic base information as a tool for economic and community development, land and natural resource management, and health and safety services. Emergency management and defense operations rely on this information. Private industry, nongovernmental organizations, and individual citizens use the same geographic data. Geographic information underpins an increasingly large part of the Nation's economy. Available geographic data often have the following problems: * They do not align with each other because layers are frequently created or revised separately, * They do not match across administrative boundaries because each producing organization uses different methods and standards, and * They are not up to date because of the complexity and cost of revision. The U.S. Geological Survey (USGS) is developing The National Map to be a seamless, continuously maintained, and nationally consistent set of online, public domain, geographic base information to address these issues. The National Map will serve as a foundation for integrating, sharing, and using other data easily and consistently. In collaboration with other government agencies, the private sector, academia, and volunteer groups, the USGS will coordinate, integrate, and, where needed, produce and maintain base geographic data. The National Map will include digital orthorectified imagery; elevation data; vector data for hydrography, transportation, boundary, and structure features; geographic names; and land cover information. The data will be the source of revised paper topographic maps. Many technical and institutional issues must be resolved as The National Map is implemented. To begin the refinement of this new paradigm, pilot projects are being designed to identify and investigate these issues. The pilots are the foundation upon which future partnerships for data sharing and maintenance will be built.

Fact Sheet

The National Map - Florida Pilot Project

Governments depend on a common set of geographic base information as a tool for economic and community development, land and natural resource management, and health and safety services. Emergency management and defense operations rely on this information. Private industry, nongovernmental organizations, and individual citizens use the same geographic data. Geographic information underpins an increasingly large part of the Nation's economy. Available geographic data often have the following problems: * They do not align with each other because layers are frequently created or revised separately, * They do not match across administrative boundaries because each producing organization uses different methods and standards, and * They are not up to date because of the complexity and cost of revision. The U.S. Geological Survey (USGS) is developing The National Map to be a seamless, continuously maintained, and nationally consistent set of online, public domain, geographic base information to address these issues. The National Map will serve as a foundation for integrating, sharing, and using other data easily and consistently. In collaboration with other government agencies, the private sector, academia, and volunteer groups, the USGS will coordinate, integrate, and, where needed, produce and maintain base geographic data. The National Map will include digital orthorectified imagery; elevation data; vector data for hydrography, transportation, boundary, and structure features; geographic names; and land cover information. The data will be the source of revised paper topographic maps. Many technical and institutional issues must be resolved as The National Map is implemented. To begin the refinement of this new paradigm, pilot projects are being designed to identify and investigate these issues. The pilots are the foundation upon which future partnerships for data sharing and maintenance will be built.

Fact Sheet

Evaluation of two juvenile salmon collection devices at Cowlitz Falls Dam, Washington, 2014

Collection of juvenile salmon at Cowlitz Falls Dam is a critical part of the effort to restore salmon in the upper Cowlitz River, Washington. Many of the fish that are not collected pass downstream and enter Riffe Lake, become landlocked, and are lost to the anadromous population. In addition to this loss, the juvenile fish collection system at Cowlitz Falls Dam, which originally consisted of four collection flumes, has failed to achieve annual collection goals since it began operating in 1996. In the years since, the collection flumes have been modified and prototype collection devices have been developed and tested, but these efforts have not substantially increased juvenile fish collection. Studies have shown that juvenile steelhead ( Oncorhynchus mykiss ), coho salmon ( Oncorhynchus kisutch ), and Chinook salmon ( Oncorhynchus tshawytscha ) tend to come close to the entrances of the collection system, but many of these fish fail to enter and eventually pass the dam through turbines or spillways. Tacoma Power developed a prototype weir box in 2009 to increase capture rates of juvenile salmon at the collection entrances. The device was evaluated with radio-tagged coho salmon (318 fish) and Chinook salmon (317 fish), and was found to have a high retention rate; 93 percent of the coho salmon, and 91 percent of the Chinook salmon that entered the device were retained and collected. However, because of safety concerns at the dam, the weir box could not be deployed near a spillway gate where the prototype was tested, so the device was altered and re-deployed at a different location where it was evaluated during 2013. During that year, discovery efficiency (number of fish detected at the entrance divided by the number of fish detected in the forebay) was 98 percent for tagged steelhead and 83 percent for tagged coho salmon. However, none of the steelhead and only 5 percent of the coho salmon entered and were collected through the weir box. These results indicated that the device was not a promising collection alternative during spring months when steelhead and coho salmon are passing the dam. However, collection conditions change during summer months when juvenile Chinook salmon are passing, so the device also was evaluated during summer 2014. In an attempt to improve overall collection efficiency, Tacoma Power developed and tested a new device in 2014, called the Upper Riffe Lake Collector (URLC). The URLC was a floating device designed to collect fish as they moved downstream after passing through turbines at Cowlitz Falls Dam. The design of the URLC included a pontoon barge that supported a large net structure designed to funnel fish into a live box where they could be removed and transported downstream of dams on the Cowlitz River.

Washington

Phase 1 technical implementation plan for the expansion of the ShakeAlert earthquake early warning system to Alaska

Executive Summary The conference report accompanying the fiscal year (FY) 2022 Consolidated Appropriations Act (Public Law 117–103) for the U.S. Department of the Interior and related agencies directed the U.S. Geological Survey (USGS) to “work with the State of Alaska to develop an implementation plan to be completed within two years in order to put ShakeAlert/Earthquake Early Warning in Alaska” (p. 29). Congress included $1 million in the FY 2022 appropriation to conduct this effort. The USGS Earthquake Hazards Program, along with partner organizations, has developed the ShakeAlert earthquake early warning (EEW) system for the West Coast, which currently operates in California, Oregon, and Washington. The purpose of the system and its alert delivery partners is to reduce the impact of earthquakes and save lives and property by delivering ShakeAlert-powered alerts that are transmitted to the public via mass notification technologies, and by providing more detailed data streams to institutional users and commercial service providers to trigger automated, user-specific, protective actions. ShakeAlert was designed in such a way that it could be expanded to other U.S. regions with high earthquake risk, after the build-out of seismic and geodetic networks to support ShakeAlert in a specified region is completed and the necessary funding is secured for long-term operation and maintenance. When an earthquake occurs, seismic waves radiate from the rupturing fault like waves on a pond. It is these waves that people feel as earthquake shaking and that can cause damage to structures. Using networks of ground-motion sensors and sophisticated computer algorithms, ShakeAlert can detect an earthquake seconds after it begins, calculate its location and magnitude, and estimate the resulting intensity of shaking. Early warnings of impending shaking are then sent to people and systems that may experience damaging shaking, allowing them to take appropriate protective actions. Depending on the user’s distance from the earthquake, alerts may be delivered before, during, or after the arrival of strong shaking. There will almost always be a region near the earthquake epicenter where alerts arrive after damaging shaking has begun. The ShakeAlert system updates its ground-motion estimates as an earthquake grows larger. In response to the FY 2022 congressional direction, the USGS worked with the State of Alaska to devise this implementation plan for ShakeAlert expansion to Alaska. The USGS engaged with the Alaska Division of Homeland Security and Emergency Management (DHS&EM) and the Alaska Division of Geological and Geophysical Surveys (DGGS). A cooperative agreement was awarded to the Alaska Earthquake Center (AEC) at the University of Alaska Fairbanks (UAF) for their contributions to the plan and their work coordinating with other networks in Alaska. The USGS engaged with the Alaska Seismic Hazards Safety Commission (ASHSC) throughout the process. The USGS also held a series of Alaska stakeholder engagements. The process of developing the implementation plan was facilitated by contracted staff from Corner Alliance, which is a government consulting firm. This implementation plan describes the details and estimates the costs for a Phase 1 expansion of the ShakeAlert system to Alaska. A geographically limited Phase 1 goal was chosen that covers the highest risk and most populated areas of Alaska. The areas proposed encompass the State’s main population centers and 90 percent of the State’s population. This Phase 1 design is considered very challenging and ambitious from the viewpoint of network operators. The lessons learned if this plan is implemented could be used to consider subsequent phases to expand EEW beyond Phase 1 in Alaska in the future. ShakeAlert is built on the foundation of the sensor networks and data processing infrastructure of the USGS-led Advanced National Seismic System (ANSS). This implementation plan calls for a total of 450 high-quality, real-time EEW-capable ANSS seismic stations in Alaska: 270 new stations, 160 upgraded stations, and 20 existing stations. These seismic station numbers are based on a station spacing of 10 kilometers (km) in urban areas, 20 km in seismic source areas that endanger population centers, and 40 km in other areas. The associated costs also include support for some EEW-capable global navigation satellite system (GNSS) stations, with a focus on improving warnings for large subduction zone earthquakes. For effective EEW, ShakeAlert requires low-latency, high-availability, robust telemetry links to deliver continuous, real-time data from field stations to the data centers. The Alaska data processing hardware infrastructure would follow the general design for fail-safe operation that is used for the ShakeAlert system on the West Coast. The ShakeAlert architecture uses two independent layers: the production layer for earthquake processing and the alert layer to make alerting decisions and serve alerts to users. This implementation plan includes two geographically separated data centers in Alaska, each with two fully independent production and alert layers using the same system design developed for the West Coast. As of March 2024, the ShakeAlert system is at version 3.0.1, with more advanced versions in the development and testing pipeline. ShakeAlert originally used two algorithms to determine the location and magnitude of earthquakes using seismic data. A third algorithm that can calculate very large magnitudes of very large earthquakes with geodetic data was added in March 2024. ShakeAlert publishes several data and alert products to meet the needs of different users. All messages include the location of the earthquake, either as a point or a line, and its magnitude. Ground-shaking estimates are published in two forms, as ground-motion contours and a map grid. Providing adequate warning time for strong shaking (the “target threshold”) requires sending alerts at a threshold lower than that strong shaking level (the “alert threshold”). The thresholds for public alerting in Alaska would be a joint USGS and State decision. To have the greatest benefit, ShakeAlert-powered alerts would be delivered to institutional users and individuals by all practical pathways. The USGS alert layer can support thousands of institutional users and alert redistributors, but the USGS does not have the mission nor the infrastructure and expertise to perform mass notifications to the public or implement automatic actions for end users of the alerts. To meet this need, ShakeAlert recruits private sector “technology enablers” that have the necessary expertise to develop end-user implementations using EEW alerts with the goal of stimulating an EEW industry. Earthquake early warning alerts are useless if people do not know how to respond to them. Although the alert messages include instructions about what to do (drop, cover, and hold on), alerts are more effective if people have been trained in advance. Messages about ShakeAlert’s capabilities, limitations, and benefits could be integrated with existing earthquake education programs, including State-run programs. Therefore, ShakeAlert would coordinate with both public and private partners and stakeholders through various partnerships and agreements to accomplish consistent and ongoing public earthquake hazard education. The estimated capital cost of completing the computing infrastructure and sensor networks for the Phase 1 ShakeAlert expansion to Alaska is approximately $66 million in 2024 dollars. The annual operation and maintenance cost of the completed system is estimated to be $12 million per year in 2024 dollars when fully built out.

Alaska

Natural gases in ground water near Tioga Junction, Tioga County, north-central Pennsylvania: Occurrence and use of isotopes to determine origins, 2005

In January 2001, State oil and gas inspectors noted bubbles of natural gas in well water during a complaint investigation near Tioga Junction, Tioga County, north-central Pa. By 2004, the gas occurrence in ground water and accumulation in homes was a safety concern; inspectors were taking action to plug abandoned gas wells and collect gas samples. The origins of the natural-gas problems in ground water were investigated by the U.S. Geological Survey, in cooperation with the Pennsylvania Department of Environmental Protection, in wells throughout an area of about 50 mi2, using compositional and isotopic characteristics of methane and ethane in gas and water wells. This report presents the results for gas-well and water-well samples collected from October 2004 to September 2005. Ground water for rural-domestic supply and other uses near Tioga Junction is from two aquifer systems in and adjacent to the Tioga River valley. An unconsolidated aquifer of outwash sand and gravel of Quaternary age underlies the main river valley and extends into the valleys of tributaries. Fine-grained lacustrine sediments separate shallow and deep water-bearing zones of the outwash. Outwash-aquifer wells are seldom deeper than 100 ft. The river-valley sediments and uplands adjacent to the valley are underlain by a fractured-bedrock aquifer in siliciclastic rocks of Paleozoic age. Most bedrock-aquifer wells produce water from the Lock Haven Formation at depths of 250 ft or less. A review of previous geologic investigations was used to establish the structural framework and identify four plausible origins for natural gas. The Sabinsville Anticline, trending southwest to northeast, is the major structural feature in the Devonian bedrock. The anticline, a structural trap for a reservoir of deep native gas in the Oriskany Sandstone (Devonian) (origin 1) at depths of about 3,900 ft, was explored and tapped by numerous wells from 1930-60. The gas reservoir in the vicinity of Tioga Junction, depleted of native gas, was converted to the Tioga gas-storage field for injection and withdrawal of non-native gases (origin 2). Devonian shale gas (shallow native gas) also has been reported in the area (origin 3). Gas might also originate from microbial degradation of buried organic material in the outwash deposits (origin 4). An inventory of combustible-gas concentrations in headspaces of water samples from 91 wells showed 49 wells had water containing combustible gases at volume fractions of 0.1 percent or more. Well depth was a factor in the observed occurrence of combustible gas for the 62 bedrock wells inventoried. As well-depth range increased from less than 50 ft to 51-150 ft to greater than 151 ft, the percentage of bedrock-aquifer wells with combustible gas increased. Wells with high concentrations of combustible gas occurred in clusters; the largest cluster was near the eastern boundary of the gas-storage field. A subsequent detailed gas-sampling effort focused on 39 water wells with the highest concentrations of combustible gas (12 representing the outwash aquifer and 27 from the bedrock aquifer) and 8 selected gas wells. Three wells producing native gas from the Oriskany Sandstone and five wells (two observation wells and three injection/withdrawal wells) with non-native gas from the gas-storage field were sampled twice. Chemical composition, stable carbon and hydrogen isotopes of methane (13CCH4 and DCH4), and stable carbon isotopes of ethane (13CC2H6) were analyzed. No samples could be collected to document the composition of microbial gas originating in the outwash deposits (outwash or 'drift' gas) or of native natural gas originating solely in Devonian shale at depths shallower than the Oriskany Sandstone, although two of the storage-field observation wells sampled reportedly yielded some Devonian shale gas. Literature values for outwash or 'drift' gas and Devonian shale gases were used to supplement the data collection. Non-native gases fr

Pennsylvania

Spatial ecology of refuge selection by an herbivore under risk of predation

Prey species use structures such as burrows to minimize predation risk. The spatial arrangement of these resources can have important implications for individual and population fitness. For example, there is evidence that clustered resources can benefit individuals by reducing predation risk and increasing foraging opportunity concurrently, which leads to higher population density. However, the scale of clustering that is important in these processes has been ignored during theoretical and empirical development of resource models. Ecological understanding of refuge exploitation by prey can be improved by spatial analysis of refuge use and availability that incorporates the effect of scale. We measured the spatial distribution of pygmy rabbit (Brachylagus idahoensis) refugia (burrows) through censuses in four 6-ha sites. Point pattern analyses were used to evaluate burrow selection by comparing the spatial distribution of used and available burrows. The presence of food resources and additional overstory cover resources was further examined using logistic regression. Burrows were spatially clustered at scales up to approximately 25 m, and then regularly spaced at distances beyond ~40 m. Pygmy rabbit exploitation of burrows did not match availability. Burrows used by pygmy rabbits were likely to be located in areas with high overall burrow density (resource clusters) and high overstory cover, which together minimized predation risk. However, in some cases we observed an interaction between either overstory cover (safety) or understory cover (forage) and burrow density. The interactions show that pygmy rabbits will use burrows in areas with low relative burrow density (high relative predation risk) if understory food resources are high. This points to a potential trade-off whereby rabbits must sacrifice some safety afforded by additional nearby burrows to obtain ample forage resources. Observed patterns of clustered burrows and non-random burrow use improve understanding of the importance of spatial distribution of refugia for burrowing herbivores. The analyses used allowed for the estimation of the spatial scale where subtle trade-offs between predation avoidance and foraging opportunity are likely to occur in a natural system.

Ecosphere

Environmental systems and management activities on the Kennedy Space Center, Merritt Island, Florida: results of a modeling workshop

In the early 1960's, the National Aeronautics and Space Administration (NASA) began purchasing 140,000 acres on Merritt Island, Florida, in order to develop a center for space exploration. Most of this land was acquired to provide a safety and security buffer around NASA facilities. NASA, as the managing agency for the Kennedy Space Center (KSC), is responsible for preventing or controlling environmental pollution from the Federal facilities and activities at the Space Center and is committed to use all practicable means to protect and enhance the quality of the surrounding environment. The Merritt Island National Wildlife Refuge was established in 1963 when management authority for undeveloped lands at KSC was transferred to the U.S. Fish and Wildlife Service. In addition to manage for 11 Federally-listed threatened and endangered species and other resident and migratory fish and wildlife populations, the Refuge has comanagement responsibility for 19,000 acres of mosquito control impoundments and 2,500 acres of citrus groves. The Canaveral National Seashore was developed in 1975 when management of a portion of the coastal lands was transferred from NASA to the National Park Service. This multiagency jurisdiction on Merritt Island has resulted in a complex management environment. The modeling workshop described in this report was conducted May 21-25, 1984, at the Kennedy Space Center to: (1) enhance communication among the agencies with management responsibilities on Merritt Island; (2) integrate available information concerning the development, management, and ecology of Merritt Island; and (3) identify key research and monitoring needs associated with the management and use of the island's resources. The workshop was structured around the formulation of a model that would simulate primary management and use activities on Merritt Island and their effects on upland, impoundment, and estuarine vegetation and associated wildlife. The simulation model is composed of four connected submodels. The Uplands submodel calculates changes in acres and structural components of vegetation communities resulting from succession, fire, facilities development, and shuttle launch depositions, as well as the quantity and quality of surface runoff and aquifer input to an impoundment and an estuary. The Impoundment submodel next determines water quality and quantity and changes in vegetation resulting from water level manipulation and prescribed burning. The Estuary submodel than determines water quality parameters and acres of seagrass beds. Finally, the Wildlife submodel calculates habitat suitability indices for key species of interest, based on vegetation conditions in the uplands and impoundments and on several hydrologic parameters. The model represents a hypothetical management unit with 2,500 acres of uplands, a 600-acre impoundment, and a 1,500-acre section of estuary. Two management scenarios were run to analyze model behavior. The scenarios differ in the frequency of shuttle launches and prescribed burning, the extent of facilities development, the amount of land disposed waste material applied, and the nature and timing of impoundment water level control. Early in a model development project, the process of building the model is usually of greater benefit than the model itself. The model building process stimulates interaction among agencies, assists in integrating existing information, and helps identify research needs. These benefits usually accrue even in the absence of real predictive power in the resulting model. Open communication occurs among the Federal, State, and local agencies involved with activities on Merritt Island and the agencies have a cooperative working relationship. The workshop provided an opportunity for all of these agencies to meet at one time and have focused discussions on the key environmental and multiagency resource management issues. The workshop framework helped to integrate information and assumptions from a number of disciplines and agencies. This integration occurred in the computer simulation model and among workshop participants as submodel linkages were developed and scenario results discussed. A number of research needs were identified at the workshop during the model building and testing exercises and associated discussions. These needs were based on the informed judgement of researchers and managers familiar with Merritt Island or similar areas, rather than on a comprehensive literature review of sensitivity analysis of the preliminary model developed at the workshop. Some of the needs can be addressed by interpreting the results of completed studies from similar geographic areas as they relate to Merritt Island, while other will require additional research studies on Merritt Island. Major research needs associated with the Upland submodel include behavior of the near-surface aquifer, factors limiting slash pine regeneration, frequency and effects of natural fire on various cover types, cumulative effects of shuttle launches, and fate in upland soils of nitrogen and phosphorous from land applied waste material. Key Impoundment submodel needs include documentation of vegetation changes in response to altered water depth, salinity, and nutrient concentrations and better specification of the functional characteristics of impoundments as chemical filters. Important information gaps identified in the Estuary submodel include a more complete analysis of factors contributing to phytoplankton abundance, evaluation of sources of turbidity other than phytoplankton, and identification and quantification of factors limiting seagrass distribution. Primary research needs associated with the Wildlife submodel include a survey of breeding habitat, production data, and harvest data for mottled ducks; data on the emigration and immigration of juvenile mullet (and other transient fish) in the impoundment; the contribution of various seagrasses to habitat requirements of sea trout; and the effects of dissolved oxygen on survival of juvenile sea trout. Ideally, the modeling workshop process is iterative in nature. Periods between workshops are used for research, data collection, and model refinement. Each workshop integrates information collected since the last workshop and produces a more credible model that is more useful in evaluating management alternatives. Participants felt that continued application of this process would help provide ongoing integration and communication among agencies and would allow each agency's planning and management activities to be viewed within the context of an overall assessment.

Report

To forage or flee: Lessons from an elk migration near a protected area

Alteration of wide-ranging wildlife migrations can drastically impact the structure and function of ecosystems, yet the causes and consequences of shifting migration patterns remain largely unknown. Management decisions made in one portion of a landscape may induce spatial and temporal shifts of wildlife use in another, creating tension among private, state, and federal lands with varying missions. Recent declines in migratory behavior have initiated studies focused primarily on spring migration, but the timing and benefits of autumn migration have received limited attention due to the difficulty in assessing the extreme asynchrony in autumnal events, although nutrition during this time period is crucial to winter survival and reproduction. Here, we used five years of data from 73 female elk (Cervus canadensis) which utilize a landscape managed by 4 federal agencies, a state, and private landowners, to identify the driving factors behind the initiation of fall migration in two subpopulations, one of which migrates to a protected area where hunting is prohibited. Most elk departed summer range prior to frost or snow, with 67% of elk that used the protected area migrating prior to the onset of archery hunting season (1 September), preemptively avoiding risk, while no elk from the other subpopulation left prior to archery season. However, departure from productive summer range prior to frost or snow, nearly two months before vegetation senescence led to an important tradeoff. Early migrants gave up 0.30% of late summer-fall integrated NDVI (iNDVI) per day when they moved to the safety of the protected area, leading to an average difference of 15.81% in iNDVI between an individual departing on 30 August (the mean departure date) versus an individual departing on 1 November. Our results suggest that in areas where migratory ungulates span multiple jurisdictions, the benefits of migratory behavior may be dramatically impacted by unevenly distributed anthropogenic disturbance. As this is a common scenario globally, our work highlights the urgent need to improve our understanding of subtle changes in migratory behavior, both spatially and temporally, which may erode the resilience of migration to future change.

Wyoming

Global exploration and production capacity for platinum-group metals from 1995 through 2015

Platinum-group metals (PGMs) are required in a variety of commercial, industrial, and military applications for many existing and emerging technologies, yet the United States is highly dependent on foreign sources of PGMs. Information on global exploration for PGMs since 1995 has been used in this study as a basis for identifying locations where the industry has determined that exploration has provided data sufficient to warrant development of a new mine or expansion of an existing operation or where a significant increase in capacity for PGMs is anticipated by 2015. Discussions include an overview of the industry and the selected sites, factors affecting mineral supply, and circumstances leading to the development of mineral properties with the potential to affect mineral supply. Of the 52 sites or regional operations that were considered in this analysis, 16 sites were producing before 1995, 28 sites commenced production from 1995 through 2010, and 8 sites were expected to begin production from 2011 through 2015 if development plans came to fruition. The United States imports PGMs primarily from Canada, Russia, South Africa, and Zimbabwe to meet increasing demand for these materials in a variety of specialized and high-tech applications. Feed sources of PGMs are changing in South Africa and Russia, which together accounted for about 89 percent of platinum production and 82 percent of palladium production in 2009. A greater amount of South African PGM capacity is likely to come from deeper, higher cost Upper Group Reef seam 2 deposits and deposits in the Eastern Bushveld area. Future Russian PGM capacity is likely to come from ore zones with generally lower PGM content and different platinum-to-palladium ratios than the nickel-rich ore that dominated PGM supply in the 1990s. Because PGM supply from Canada and Russia is derived as a byproduct of copper and nickel mining, the PGM supply from these countries is influenced by economic, environmental, political, and technological factors affecting exploration for and development of copper and nickel, as well as factors affecting the PGM industry. The recovery of PGMs from mill tailings since 2004 and the recycling of PGMs from catalytic converters, electrical components, and jewelry has increased since 1995 so that recycled PGMs recovered from these products accounted for about 30 percent of the supply of platinum worldwide and 29 percent of the supply of palladium worldwide in 2010. Economic and geopolitical conditions have influenced PGM supply and demand. The global recession of 2008 and 2009 temporarily decreased demand for PGMs and constrained PGM mine exploration and development, at least through 2010. Legislation regulating the structure of the mining sector has affected mining in Russia, South Africa, and Zimbabwe. Stricter vehicle emissions standards in established markets since the 1980s have led to mandatory use of pollution control devices, such as catalytic converters, that contain PGMs and are required on vehicles in expanding markets, such as China and India. It is expected that South Africa, Russia, Canada, and Zimbabwe will continue to be the principal sources of PGM at least for the next decade. Based on this review of the PGM industry, the world’s platinum capacity, expressed in terms of recoverable platinum metal, increased from 1995 through 2010 by 77,000 kilograms (kg) in South Africa, 9,000 kg in Zimbabwe, 6,000 kg in Russia, 2,000 kg in Botswana, and 2,000 kg in Canada. For the same period, palladium capacity worldwide increased by 44,000 kg in South Africa, 22,000 kg in Russia, 8,000 kg in Canada, 8,000 kg in the United States, 7,000 kg in Zimbabwe, and 3,000 kg in Botswana. Platinum capacity worldwide is expected to further increase by 24,000 kg in South Africa, 9,000 kg in Russia, 3,000 kg in Canada, and 2,000 kg in Zimbabwe from 2011 through 2015. Palladium capacity worldwide is likewise expected to increase an additional 16,000 kg in Russia, 14,000 kg in South Africa, 4,000 kg in Zimbabwe, and 1,000 kg in Canada if new or expanded mine and associated processing capacity comes into production as planned. It is likely that the magnitude of these changes in PGM capacity has been influenced by such factors as the global economy, electrical capacity shortages and mine safety concerns in South Africa, and geopolitical conditions in the major PGM producing countries.

Scientific Investigations Report