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At least 865 records · Page 48Linked to original sources

Records and logs of selected wells and test holes, chemical analyses of water, and water levels in observation wells in southeastern New Hampshire

The area covered by this report (fig. 1) includes about 390 square miles of southeastern New Hampshire adjacent to the Atlantic Ocean. It lies between Massachusetts on the south and Maine on the north and east, and it is bounded on the east by the Atlantic Ocean and on the west by a line drawn approximately northward from Atkinson at the Massachusetts border to Farmington near the Maine border. The area includes parts of Rockingham and Strafford Counties. The report presents basic data collected as part of an investigation of the geology and ground-water resources of southeastern New Hampshire by the U. S. Geological Survey in cooperation with the New Hampshire Water Resources Board. These data have been prepared for release in order to make available to the public basic ground-water data that will be useful in the planning of water-resources development. Most of the data contained in this report were collected by Edward Bradley during the period September 1953 to January 1958.

New Hampshire↗

Aerial profiling of terrain to define stream-valley geometry: study report

A six-month engineering analysis was performed by The Charles Stark Draper Laboratory, Inc., at the request of the U. S. Geological Survey, to investigate the suitability of an airborne instrument package based on inertial techniques to serve as the datum for a laser altimeter in a system for aerial profiling of terrain to determine selected features of stream-valley geometry to an accuracy of ± 0.5 ft. in the vertical coordinate and ± 10 ft. in the horizontal coordinates. Feasible system configuration features a high performance inertial platform incorporating an integral laser tracker, pointing and ranging on retroreflectors on the ground, in order to provide the frequent updates needed to meet the accuracy requirements. In all environments except those of severe gravity gradients the nominal two- by twenty-mile survey area can be covered using three ground-surveyed retroreflectors, interspersed with several unlocated retroreflectors that are surveyed in by the airborne system along a longitudinal path within the river valley when the aircraft arrives over the site. Subsequent transverse profiling runs (traverses that may be spaced as close as one-quarter mile apart) are flown using, in turn, all retroreflectors as updating position references. Pointing and range information from the tracker are optimally combined with the on-board inertial measurements and available gravity data to provide position information and serve as the height datum for a terrain-clearance measuring laser altimeter. Data-logging means and operator display, as well as steering commands to the aircraft autopilot, are provided. The system configuration is capable of operating in single- or twin-engine aircraft including helecopters. It is recommended that work proceed into the design phase.

Open-File Report↗

Preliminary report on the mineral resources of the Powderhorn Instant study area, Gunnison and Hinsdale counties, Colorado

The Powderhorn Instant Study Area covers approximately 51,000 acres of land under BLM administration located about 80 km (50 mi) southwest of Gunnison, Colorado. A mineral resource survey, made in 1979 by the U.S. Geological Survey and the U.S. Bureau of Mines, indicates that both the mineral potential and the energy potential for the Powderhorn Instant Study Area are low. This report is based on geologic and geochemical investigations, examination of prospects, and an aeromagnetic survey. Spectrographic analyses were made of approximately 120 stream-sediment and rock samples. No mining districts are located within the study area.

Colorado↗

Index of surface-water stations in Texas, January 1982

The U.S. Geological Survey's investigations of the water resources of Texas are conducted in cooperation with the Texas Department of Water Resources, river authorities, cities, counties, U.S. Army Corps of Engineers, U.S. Bureau of Reclamation, International Boundary and Water Commission, and others.

Texas↗

The Giles County, Virginia, seismogenic zone-- Seismological results and geological interpretations

This paper describes and interprets a newly-recognized 40-km-long seismogenic zone, which is inferred to have been the locus of a damaging earthquake in 1897. That shock was the second largest known to have occurred in the southeastern United States (MMI VIII, m b estimated at 5.8, felt over 725,000 km 2 ). It struck Giles County in southwestern Virginia, and a recurrence would affect populous regions on and near the central Atlantic seaboard. This paper attempts to aid in evaluating that hazard by presenting and synthesizing new seismological data with geological inferences and deductions. A five-station, 60-km aperture seismic network has been in operation in the Giles County locale since early 1978. For the subsequent 3-year monitoring period, 10 microearthquakes (M < 2) have been detected. Eight of those 10 events, plus an additional 4 relocated felt earthquakes (3.2 < M < 4.1; 1959-1976) have a tabular distribution centered at Pearisburg, Virginia. That distribution is about 40 km long, 10 km wide, strikes N. 43° E., and has a nearly vertical extent of from 5 km to 25 km in depth. Thus, a Giles County seismogenic zone is defined presently by 12 earthquakes that span 4 orders of magnitude (0 < M < 4) and 2 decades of time (1959-1980). We conclude that the 1897 earthquake occurred on that seismogenic zone. From the orientation of the tabular zone, from evidence that greatest horizontal compressive stress trends east-northeasterly at seismogenic depths in and near Giles County and from sparse P-wave first-motion data, we infer that the monitored microseismicity probably occurs by right-reverse motion on the seismogenic zone, with the southeast side dropping down with respect to the northwest side. In the Giles County locale, the upper 3-6 km of the crust are Paleozoic sedimentary rocks that have moved some tens of kilometers northwest on nearly horizontal detachment faults. The above-mentioned reliable hypocenters for the region lie below the deepest likely detachment, indicating that Giles County seismicity probably has no simple relationship to surface geology. Since Precambrian time, three deformational episodes could have formed steep faults under today's surface structures, at the observed hypocentral depths. These episodes were as follows: (1) As the Iapetus Ocean (Atlantic's predecessor) opened in late Precambrian or early Paleozoic time, northeast-striking normal faults formed, probably at the inferred Iapetan continental edge in central Virginia and at least as far northwest of that locus as Giles County. (2) In late Paleozoic time, detachment faults loaded the crust with several kilometers of overthrust sedimentary rocks, perhaps forming northeast-striking thrust-load faults in a brittle analogue of isostatic depression caused by thrust masses and much lighter continental glaciers. (3) As the Atlantic Ocean opened in Mesozoic time, other northeast-striking normal faults formed on the present continental margin and inland of it. The N. 43° E.-striking seismogenic zone seems most likely to have resulted from compressional reactivation of an Iapetan normal fault, which also may have been reactivated by late Paleozoic compression and Mesozoic extension. First, the seismogenic zone probably does not occur on a thrust-load fault. The zone underlies detached structures of southern Appalachian orientations (east-northeast), but those structures are not known to be displaced where they cross the zone. Thus, if the zone occurs on a thrust-load fault, the fault and its coeval causative central Appalachian detachments would pre-date the southern Appalachian structures. That deduction contradicts stratigraphic and structural estimates of relative ages of southern and central Appalachian detachments. Second, the zone probably does not result from a Mesozoic normal fault, because known locations of Mesozoic normal faults and grabens are well to the southeast of Giles County. Not yet known is where else in the East reactivated Iapetan normal faults might generate shocks similar to that of 1897. However, our analysis enables us to suggest specific geological and geophysical investigations that may produce results useful in answering that question. Such investigations can concentrate on defining the area of probable occurrence of other Iapetan normal faults, and on determining whether the one inferred to underlie Giles County is uniquely active or is typical of others that might exist elsewhere.

Virginia↗

Geohydrologic data from sandstone aquifers in southwestern Kansas

Data collected during a reconnaissance investigation of the geology and hydrology of sandstone aquifers provide useful information in the study of, and planning for, water-resources development in a 17,400 square-mile area in 26 counties of southwestern Kansas. The aquifers consist chiefly of saturated sandstones that occur in Upper Permian, Upper Jurassic, and Lower and Upper Cretaceous rocks. In parts of southwestern Kansas, the sandstone aquifers already serve as the principal or secondary source of ground water for irrigation and other uses. Data indicate that water may be available for development in sandstone aquifers in other parts of the study area. In still other areas, water from wells in sandstone aquifers may not be of a suitable quality for some purposes. The data provided include records of selected wells, lithologic logs of test holes and wells, selected formation surfaces and sandstone thicknesses , chemical analyses of water from selected wells, and water levels in observation wells. (USGS)

Open-File Report↗

Index of surface-water stations in Texas, January 1984

The U.S. Geological Survey's investigations of the water resources of Texas are conducted in cooperation with the Texas Department of Water Resources, river authorities, cities, counties, U.S. Army Corps of Engineers, U.S. Bureau of Reclamation, International Boundary and Water Commission, and others. Investigations are under the general direction of C. W. Boning, District Chief, Texas District. The Texas District office is located in the Federal Building, 300 East 8th Street, Austin, Texas 78701. As of January 1, 1984, 399 stream-gaging, 86 reservoir-contents, 19 stage, 2 periodic discharge through range, 42 flood-hydrograph partial-record, 15 floodprofile partial-record, 34 low-flow partial-record, 11 crest-stage partial-record, 11 tide-level , 60 daily chemical-qual ity, 27 continuous-recording water-quality, 187 periodic chemical-qual ity, 175 periodic organic-quality, 60 pesticides, 1 sediment, 43 periodic sediment, 109 periodic biological, 28 continuous-recording water temperature, and 37 national stream-quality accounting network stations were in operation. Plate 1 shows the location of surface-water streamflow or reservoircontent and chemical-qual ity or sediment stations in Texas. Plate 2 shows the location of partial-record surface-water stations. This index shows the station number and name, latitude and longitude, type of data collected, and the office principally responsible for the data collection (table 1). An 8-digit permanent numerical designation for gaging stations has been adopted on a nationwide basis; stations are numbered and listed in downstream order. In the downstream direction along the main stem, all stations on a tributary entering above a main-stem station are listed before that station. A tributary entering between two main-stem stations is listed between them. A similar order is followed in listing stations on first rank, second rank, and other ranks of tributaries. To indicate the rank of any tributary on which a gaging station is situated and the stream to which it is an immediate tributary, each indention in the listing of gaging stations represent one rank. This downstream order and system of indention show which gaging stations are on tributaries between any two stations on a main stem and the rank of the tributary on which each gaging station is situated. On plates 1 and 2 the 8-digit station number is abbreviated because of space limitation.

Texas↗

Index of surface-water stations in Texas, January 1985

The U.S. Geological Survey's investigations of the water resources of Texas are conducted in cooperation with the Texas Department of Water Resources, river authorities, cities, counties, U.S. Army Corps of Engineers, U.S. Bureau of Reclamation, International Boundary and Water Commission, and others. As of January 1, 1984, 404 streamflow, 89 reservoir-contents, 32 stage, 10 crest-stage partial-record, 2 periodic discharge through range, 31 flood-hydrograph partial-record, 15 flood-profile partial-record, 41 low-flow partial-record, 11 tide-level, 49 daily chemical-quality, 26 continuous-recording water-quality, 100 periodic biological, 19 lake surveys, 170 periodic organic and (or) nutrient, 3 periodic insecticide, 57 periodic pesticide, 25 automatic sampler, 152 periodic minor elements, 147 periodic chemical-quality y 102 periodic physical-organic, 7 continuous-recording four-parameter water-quality, 3 sediment, 40 periodic sediment, 28 continuous-recording temperature, and 38 national stream-quality accounting network stations were in operation. Plate 1 shows the location of surface-water streamflow or reservoir content and chemical-quality or sediment stations in Texas. Plate 2 shows the location of partial-record surface-water stations. This index shows the station number -and name, latitude and longitude, type of data collected, and the office principally responsible for the data collection (table 1). An 8-digit permanent numerical designation for gaging stations has been adopted on a nationwide basis; stations are numbered and listed in downstream order. In the downstream direction along the main stem, all stations on a tributary entering above a main-stem station are listed before that station. A tributary entering between two main-stem stations is listed between them. A similar order is followed in listing stations on first rank, second rank, and other ranks of tributaries. To indicate the rank of any tributary on which a gaging station is situated and the stream to which it is an immediate tributary, each indention in the listing of gaging stations represent one rank. This downstream order and system of indention show which gaging stations are on tributaries between any two stations on a main stem and the rank of the tributary on which each gaging station is situated. On plates 1 and 2, the 8-digit station number is abbreviated because of space limitation.

Texas↗

Water-resources activities of the U.S. Geological Survey in New Mexico, fiscal year 1986

All U.S. Geological Survey hydrologic investigations in the New Mexico District in progress during fiscal year 1986 are summarized. The summaries include sections on the problem addressed, the objective and approach of the investigation, progress of the investigation and plans for 1986 fiscal year, and reports published as a result of the investigation. Water conditions in New Mexico during the 1985 water year are briefly described. Reports released during 1985 are listed. The New Mexico District office organization, cooperating agencies, and types of funding for the District operation are also summarized. (USGS)

Open-File Report↗

Index of stations— Surface-water data-collection network of Texas, September 1993

The U.S. Geological Survey's investigations of the water resources of Texas are conducted in cooperation with the Texas Water Development Board, river authorities, cities, counties, U.S. Army Corps of Engineers, Bureau of Reclamation, International Boundary and Water Commission, and others. Investigations are under the general direction of R.O. Hawkinson, District Chief, Texas District. The address of the Texas District office is 8011 Cameron Road, Austin, TX 78754. As of September 30, 1993, the surface-water data-collection network of Texas (table 1 at end of the report) included 342 continuous-recording streamflow stations (D), 36 gage-height record only stations (G), 18 crest-stage partial-record stations (C), 62 floodhydrograph partial-record stations (H), 28 low-flow partial-record stations (L), 2 continuous-recording temperature stations (Ml), 12 continuous-recording temperature and conductivity stations (M2), 5 continuous-recording temperature, conductivity, and dissolved oxygen stations (M3), 20 continuous-recording temperature, conductivity, dissolved oxygen, and pH stations (M4), 23 daily chemical-quality stations (Q), 158 periodic chemical-quality stations (Qp), 20 lake surveys for water quality (Qs), and 75 continuous or daily reservoir-content stations (R). Plate 1 shows the location of the stations listed in table 1. Table 1 shows the station number and name, latitude and longitude, type of station, and the office principally responsible for collection of the data. An 8-digit permanent numerical designation for all gaging stations has been adopted on a nationwide basis; stations are numbered and listed in downstream order. In the downstream direction along the main stem, all stations on a tributary entering between two main-stem stations are listed between them. A similar order is followed in listing stations by first rank, second rank, and other ranks of tributaries. The rank of any tributary with respect to the stream to which it is an immediate tributary is indicated by an indention in the table. Each indention represents one rank. This downstream order and system of indention shows which gaging stations are on tributaries between any two stations on a main stem and the rank of the tributary on which each gaging station is situated.

Texas↗

Simulation of ground-water flow of the coastal plain aquifers in parts of Maryland, Delaware, and the District of Columbia

Geomorphic processes and the aquatic habitat of the Redwood Creek basin were studied extensively between 1973 and 1983. This volume contains 22 separate articles by 32 investigators who studied geology, major storms, timber harvesting and its role on accelerating erosion, mass movement, fluvial erosion, sediment transport and storage, stream channel response to storms and landuse, stream habitat, and stream chemistry. This research describes a rapidly eroding landscape that is sensitive to effects of both landuse and major storms.

Delaware, District of Columbia, Maryland↗

The Coalinga, California, earthquake of May 2, 1983

At 2342 G.m.t. May 2, 1983, a magnitude (ML) 6.7 earthquake occurred about 12 km northeast of the town of Coalinga, approximately halfway between Los Angeles and San Francisco. The shock was felt from Los Angeles to 200 km north of Sacramento and as far east as Las Vegas. Unlike other well-documented, major earthquakes in California in the 20th century, this event was not associated with any previously known or suspected active fault. Comprehensive geologic and geophysical investigations begun soon after the event have demonstrated the absence of a near-surface fault responsible for the earthquake. Instead, the earthquake was closely associated with a fault zone concealed beneath folds developed along the structural boundary between the Coast (Diablo) Ranges and the San Joaquin Valley.

California↗