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The Office of the Assistant Division Chief for Research, National Mapping Division, develops computer software for the solution of geometronic problems in the fields of surveying, geodesy, remote sensing, and photogrammetry. Software that has been developed using public funds is available on request for a nominal charge to recover the cost of duplication.
Established in 1879, to build and organize a collection of scientific materials in the earth sciences, the U.S. Geological Survey (USGS) Library is the largest earth sciences collection in the world. The USGS Library System is managed by the Geographic Information Office (GIO), Information Policy and Services Office, and includes four libraries in Reston, Va., Denver, Colo., Menlo Park, Calif., and Flagstaff, Ariz. The library holds over one million books and journals, 700,000 maps, 370,000 microforms, 270,000 pamphlets, and 250,000 photographs. In addition to the four libraries managed by the GIO, the USGS has smaller libraries in other locations with collections closely related to the specialized research of their local USGS scientists. The USGS Library System supports the research of USGS scientists by providing access to worldwide information resources. While continuing to build and maintain the large collections of maps, books, and periodicals, the USGS Library system is evolving from a traditional library to a more "virtual library." USGS employees, wherever they are located, have desktop access to an increasing wealth of electronic resources 24 hours a day, 7 days a week.
According to the Federal Communications Commission, millions of Americans in rural parts of the country currently lack access to broadband (high-speed, always-on internet). Federal and State agencies have launched initiatives to enhance broadband access in rural America. High-resolution light detection and ranging (lidar) data can play a role in improving maps of broadband accessibility and helping to strengthen the broadband communications network. Lidar underpins signal propagation analyses to determine where broadband signals from communication towers can and cannot reach across the landscape and can be used to determine optimal siting of new towers and cell stations to increase broadband coverage.
The Greater Platte River Basin area spans a central part of the Midcontinent and Great Plains from the Rocky Mountains on the west to the Missouri River on the east, and is defined to include drainage areas of the Platte, Niobrara, and Republican Rivers, the Rainwater Basin, and other adjoining areas overlying the northern High Plains aquifer. The Greater Platte River Basin contains abundant surficial deposits that were sensitive to, or are reflective of, the climate under which they formed: deposits from multiple glaciations in the mountain headwaters of the North and South Platte Rivers and from continental ice sheets in eastern Nebraska; fluvial terraces (ranging from Tertiary to Holocene in age) along the rivers and streams; vast areas of eolian sand in the Nebraska Sand Hills and other dune fields (recording multiple episodes of dune activity); thick sequences of windblown silt (loess); and sediment deposited in numerous lakes and wetlands. In addition, the Greater Platte River Basin overlies and contributes surface water to the High Plains aquifer, a nationally important groundwater system that underlies parts of eight states and sustains one of the major agricultural areas of the United States. The area also provides critical nesting habitat for birds such as plovers and terns, and roosting habitat for cranes and other migratory birds that travel through the Central Flyway of North America. This broad area, containing fragile ecosystems that could be further threatened by changes in climate and land use, has been identified by the USGS and the University of Nebraska-Lincoln as a region where intensive collaborative research could lead to a better understanding of climate change and what might be done to adapt to or mitigate its adverse effects to ecosystems and to humans. The need for robust data on the geologic framework of ecosystems in the Greater Platte River Basin has been acknowledged in proceedings from the 2008 Climate Change Workshop and in draft reports by researchers developing a multidisciplinary science plan for the Greater Platte River Basin.
Introduction National parks and preserves in the South Atlantic-Gulf Region contain valuable coastal habitats such as tidal wetlands and mangrove forests, as well as irreplaceable historic buildings and archeological sites located in low-lying areas. These natural and cultural resources are vulnerable to accelerated sea-level rise and escalating high tide flooding events. Through a Natural Resources Preservation Program-funded project during 2021–23, the U.S. Geological Survey, in collaboration with the National Park Service, estimated the probability of inundation at Big Cypress National Preserve, Florida, and several other parks under various sea-level rise scenarios and contemporary high tide flooding thresholds. The maps produced for this effort can be used to assess potential habitat change and explore how infrastructure and cultural resources within the park may be exposed to future flooding-related hazards.
Introduction National parks and preserves in the South Atlantic-Gulf Region contain valuable coastal habitats such as tidal wetlands and mangrove forests, as well as irreplaceable historic buildings and archeological sites located in low-lying areas. These natural and cultural resources are vulnerable to accelerated sea-level rise and escalating high tide flooding events. Through a Natural Resources Preservation Program-funded project during 2021–23, the U.S. Geological Survey, in collaboration with the National Park Service, estimated the probability of inundation at Biscayne National Park, Florida, and several other parks under various sea-level rise scenarios and contemporary high tide flooding thresholds. The maps produced for this effort can be used to assess potential habitat change and explore how infrastructure and cultural resources within the park may be exposed to future flooding-related hazards.
The area in the Oman ophiolite containing the volcanic-hosted Bayda and Aarja massive sulfide deposits exposes a cross section of ocean crust and reveals to an unprecedented extent the fossil zones of hydrothermal upwelling that fed these sea-floor deposits. The fossil discharge zones are elongate areas of alteration and mineralization characterized by numerous small (metres to tens of metres in length), linear, discontinuous gossans. The gossans result from oxidation of hydrothermal pyrite replacing primary igneous phases and filling voids and fractures in the altered host rocks. The two deposits have separate discharge zones that appear to be sub-sea-floor extensions of their stockworks. The Bayda zone extends through the volcanic section into the upper sheeted dike complex and is interpreted as having formed on the ridge crest above an axial magma chamber; the Aarja zone terminates against a plagiogranite pluton that intrudes the lower volcanic section and is thought to have formed after Bayda in an off-axis environment. Structural, stratigraphic, and compositional characteristics of the Bayda and Aarja massive sulfide bodies are consistent with this interpretation. The geometry of the discharge zones suggests that in both cases upfiow occurred in broad zones (at least 400-600 m wide) that were elongated along strike (i.e., parallel to the spreading axis).
Techniques of architectural element analysis and lateral profiling have been applied to the fluvial Westwater Canyon Member of the Morrison Formation (Jurassic) in southern San Juan Basin. On a large scale, the sandstone-body architecture consists mainly of a series of tabular sandstone sheets 5–15 m thick and hundreds of meters wide, separated by thin fine-grained units. Internally these sheets contain lateral accretion surfaces and are cut by channels 10–20 m deep and at least 250 m wide. On a more detailed scale, interpretations made from large-scale photomosaics show a complex of architectural elements and bounding surfaces. Typical indicators of moderate- to high-sinuosity channels (lateral accretion deposits) coexist in the same outcrop with downstream-accreted macroform deposits that are typical of sand flats of low-sinuosity, multiple-channel rivers. Broad, deep channels with gently to steeply dipping margins were mapped in several of the outcrops by carefully tracing major bounding surfaces. Locally thick accumulations of plane-laminated and low-angle cross-laminated sandstone lithofacies suggest rapid flow, probably transitional to upper flow regime conditions. Such a depositional style is most typical of ephemeral rivers or those periodically undergoing major seasonal (or more erratic) stage fluctuations, an interpretation consistent with independent mineralogical evidence of aridity. Fining-upward sequences are rare in the project area, contrary to the descriptions of Campbell (1976). The humid alluvial fan model of Galloway (1978) cannot be substantiated and, similarly, the architectural model of Campbell (1976) requires major revision. Comparisons with the depositional architecture of the large Indian rivers, such as the Ganges and Brahmaputra, still seem reasonable, as originally proposed by Campbell (1976), although there is now convincing evidence for aridity and for major stage fluctuations, which differs both from those modern rivers and Campbell's interpretation.
T he U.S. Geological Survey’s Flagstaff Science Campus is focused on interdisciplinary study of the Earth and solar system, and has the scientific expertise to detect early environmental changes and provide strategies to minimize possible adverse effects on humanity. The Flagstaff Science Campus (FSC) is located in Flagstaff, Arizona, which is situated in the northern part of the State, home to a wide variety of landscapes and natural resources, including (1) young volcanoes in the San Francisco Volcanic Field, (2) the seven ecological life zones of the San Francisco Peaks, (3) the extensive geologic record of the Colorado Plateau and Grand Canyon, (4) the Colorado River and its perennial, ephemeral, and intermittent tributaries, and (5) a multitude of canyons, mountains, arroyos, and plains. More than 200 scientists, technicians, and support staff provide research, monitoring, and technical advancements in planetary geology and mapping, biology and ecology, Earth-based geology, hydrology, and changing climate and landscapes. Scientists at the FSC work in collaboration with multiple State, Federal, Tribal, municipal, and academic partners to address regional, national, and global environmental issues, and provide scientific outreach to the general public.
In the late spring of 2008, the Chevron-led Gulf of Mexico Gas Hydrate Joint Industry Project (JIP) expects to conduct an exploratory drilling and logging campaign to better understand gas hydrate-bearing sands in the deepwater Gulf of Mexico. The JIP Site Selection team selected three areas to test alternative geological models and geophysical interpretations supporting the existence of potential high gas hydrate saturations in reservoir-quality sands. The three sites are near existing drill holes which provide geological and geophysical constraints in Alaminos Canyon (AC) lease block 818, Green Canyon (GC) 955, and Walker Ridge (WR) 313. At the AC818 site, gas hydrate is interpreted to occur within the Oligocene Frio volcaniclastic sand at the crest of a fold that is shallow enough to be in the hydrate stability zone. Drilling at GC955 will sample a faulted, buried Pleistocene channel-levee system in an area characterized by seafloor fluid expulsion features, structural closure associated with uplifted salt, and abundant seismic evidence for upward migration of fluids and gas into the sand-rich parts of the sedimentary section. Drilling at WR313 targets ponded sheet sands and associated channel/levee deposits within a minibasin, making this a non-structural play. The potential for gas hydrate occurrence at WR313 is supported by shingled phase reversals consistent with the transition from gas-charged sand to overlying gas-hydrate saturated sand. Drilling locations have been selected at each site to 1) test geological methods and models used to infer the occurrence of gas hydrate in sand reservoirs in different settings in the northern Gulf of Mexico; 2) calibrate geophysical models used to detect gas hydrate sands, map reservoir thicknesses, and estimate the degree of gas hydrate saturation; and 3) delineate potential locations for subsequent JIP drilling and coring operations that will collect samples for comprehensive physical property, geochemical and other analyses
The State Geological Surveys of Illinois, Indiana, Michigan, and Ohio joined with the U.S. Geological Survey (USGS, under the Earth Surface Dynamics Program) to form the Central Great Lakes Geologic Mapping Coalition. These four States have a similar geologic heritage and need to address common societal issues about land and water resources, the environment, and geologic hazards. By pooling their expertise and resources, the five Geological Surveys can address these issues more effectively than could any one survey.
Abandoned and unrecorded wells may act as conduits for the contamination of groundwater supplies by oil field brines and other pollutants. The casings of abandoned wells eventually develop leaks, which, if not properly plugged, can allow pollutants to reach freshwater aquifers that supply drinking water. Sources of pollutants include brine ponds, landfill sites, agricultural activities, industrial activities, illegal disposal sites, or accidental spills. The problem is particularly acute in regions where there are old petroleum fields or where water wells have been extensively used for agricultural irrigation. Even urban areas can contain wells that were abandoned and concealed during development. Carefully designed ground magnetic or aeromagnetic surveys can be used to locate abandoned wells by mapping the magnetic disturbances or "anomalies" produced by their steel well casings. The U.S. Geological Survey (USGS) can, at the request of other Federal, State, or local agencies, conduct, process, and interpret such surveys, or it can aid in the design and monitoring of contracts for such surveys.
Federal, State, and local response and management personnel must have current, reliable, and easily accessible geographic information and maps to prepare for, respond to, or recover from emergency situations. In life-threatening events, such as earthquakes, floods, or wildland fires, geographic information is essential for locating critical infrastructure and carrying out evacuation and rescue operations. The USGS promotes partnerships to ensure that base map data are up to date, readily available, and shareable among local, state, and National users. The National Map enables other government agencies, private industry, and the public to link and share additional data that provide even more information. These efforts with state and local governments have helped standardize the data by reducing data inconsistencies between neighboring jurisdictions and will help fill in the gaps for those places where data are lacking.
Coral ecosystems and their natural capital are at risk. Greenhouse gas emissions, overfishing, and harmful land-use practices are damaging our coral reefs. Overwhelming scientific evidence indicates that the threats are serious, and if they are left unchecked, the ecological and social consequences will be significant and widespread. Although the primary stressors to coral ecosystems are known, science-based strategies are needed to more accurately explain natural processes and forecast human-induced change. Collaborations among managers and scientists and enhanced mapping, monitoring, research, and modeling can lead to effective mitigation plans. U.S. Geological Survey scientists and their partners assess coral ecosystem history, ecology, vulnerability, and resiliency and provide study results to decisionmakers who may devise policies to sustain coral resources and the essential goods and services they provide.
The Malaspina district extends about 50 miles along the north shore of the Gulf of Alaska from Icy Bay and the Guyot Glacier on the west to Yakutat Bay and Disenchantment Bay on the east (see index map). The district includes a coastal lowland flanked on the north by a belt of rugged foothills, the higher ridges and peaks of which rise to altitudes of 1,000 to 6,000 feet. The southern front of the St. Ell as Mountains rises abruptly at the northern margin of the foothills belt, about 30 miles from the coast, culminating in Mount St. Elias (18,008 ft.). The Malaspina Glacier, the dominant feature of the Malaspina district, has long been regarded as the type example of the piedmont glacier. This huge ice sheet covers an area of about 840 square miles of the coastal lowland, rising gradually from an altitude of 100 feet or less at the outer margin to altitudes ranging from 1,000 feet to 2,000 feet at the southern margin of the foothills belt. The Malaspina Glacier is of special interest to glaciologists because its strikingly developed morainic banding offers clues to the nature of glacier movement. The processes of wastage and deposition at the stagnant margin of Malaspina Glacier can be compared with the mode of retreat of the former continental ice sheets; much can be learned here of the origin of the deposits formed along a stagnant ice margin.
This map was compiled as part of a U.S. Geological Survey project to portray the character and thickness of glacial deposits east of the Rocky Mountains. It is a preliminary map, compiled at a scale of 1:250,000 from sources of differing type and quality (fig. I, table 1). County drift-thickness maps produced by the Ohio Geological Survey are the most reliable source of data used. These county maps, either published or in manuscript form, were available for 36 of the 72 counties that contain glacial or glacially related deposits more than 50 ft thick. An earlier, reconnaissance drift-thickness map of northwestern Ohio (Ohio Department of Natural Resources, 1960) provided data for parts of 12 additional counties. Published maps of bedrock topography were utilized for 9 counties and for parts of 6 counties. The computation of drift thickness in these counties is less reliable then the drift-thickness maps published by the Ohio Geological Survey because the bedrock topography maps, most of which are at least 20 years old, were compiled from a more limited set of data. In the remaining counties, only well-log data were available. Drift-thickness data in these counties are the least reliable; the determination of thickness trends was commonly guided by the configuration of preglacial drainage channels (as drawn by Stout and others, 1943) and by topography. Throughout the glaciated areas of Ohio, and especially near the glacial margin, a network of drainage channels is buried by glacial drift. Some of these channels arc of a preglacial age while others were formed during interglacial periods; some were cut into the bedrock by rivers— either preglacial rivers or meltwater streams flowing along the glacial margin—while others, such as the lower Cuyahoga River valley, may have been overdeepened by the erosive power of glacial ice. The thickest deposits of drift in the state occur in the lower Cuyahoga River valley near Lake Erie, and above the buried valley in west-central Ohio that has been historically considered a part of the Teays Valley. The thickest drift reliably measured in Ohio to date is 602 ft in a drill hole near Cleveland. In contrast to the extreme variations in drift thickness encountered in the vicinity of buried channels, drift on the upland arcus is generally thinner and the variations in thickness are much less pronounced. Worthy of note, however, are three large areas where the drift sheet is relatively thick. In northwestern Ohio, a large volume of drift was deposited along the flanks of the Erie ice lobe (fig. 2) near the interlobate position with the Saginaw lobe to the northwest; drift thickness there exceeds 200 ft. Thick drift was also deposited in a roughly cast-west band across the Miami lobe. The mechanism that produced this band of thick drift is not obvious, but it may have been influenced in part by bedrock topography. Bedrock control of drift thickness is more clearly indicated to the cast of Columbus, along the eastern flank of the Scioto lobe, where ice slow was resisted by rocks of the Allegheny plateau. The edge of the plateau, or the Allegheny escarpment, is obscured by glacial deposits but its likely position (Fenneman, 1938; Stout and others, 1913; Dove, 1960; and Root and others, 1961) is shown on the map. Southward from the ice margin's reentrant position in southern Richland County, ice flowing eastward from the Scioto lobe encountered the topographically higher plateau, which constrained the ice and caused drift to accumulate in significant thicknesses just to the west of the escarpment.
Governments depend on a common set of base geographic information as a tool for economic and community development, land and natural resource management, and health and safety services. Emergency management and homeland security applications 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.
Governments depend on a common set of base geographic information as a tool for economic and community development, land and natural resource management, and health and safety services. Emergency management and homeland security applications 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.