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At least 559 records · Page 31Linked to original sources
USGS1968

Ground-water exploration using the resistivity method on the Hawaiian Islands of Oahu and Hawaii

Thirty-six resistivity soundings were made on the islands of Oahu and Hawaii to determine the applicability of galvanic resistivity methods for locating fresh-water aquifers in the State of Hawaii. Soundings were made on the northwestern part of the island of Oahu near the town of Waialua and on the island of Hawaii on the "saddle" area near Pohekuloa and the Humuula sheep station. On Oahu, the geoelectrical study indicates that correlation among four stratigraphic units underlain by a vesicular basalt basement is possible. The electrical soundings indicate that it is feasible to determine the approximate depth to the fresh-saline water interface within the basalt. Two Schlumberger soundings with electrode spacings, AB/2, reaching 6,000 feel give sounding curves of the maximum and minimum type whose terminal branches indicate that the true resistivity of basalts saturated with sea water, in the survey area on Oahu, is about 30-40 ohm-m. On the island of Hawaii, an exploratory well drilled in basalt to a depth of 1,001 feet proved to be dry. In the area of this well, two deep soundings were made using the Schlumberger and the equatorial arrays. Although additional soundings at various orientations and larger spacings are needed, there appears to be a conductive layer below 1,600 feet which may represent basalt saturated with fresh water.

Hawaii↗
USGS1968

Ground-water exploration in the Bosque del Apache Grant, Socorro County, New Mexico

Test drilling along the Rio Grande in the Bosque del Apache Grant in Socorro County, New Mexico has shown that the area is hydrologically complex and that the quality of the ground water varies from saline to fresh within short distances both laterally and vertically. Nearly all of the riverside land in the Grant is occupied by the migratory waterfowl refuge of the Bosque del Apache National Wildlife Refuge. Potable and near-potable water is obtained from 12 wells in this area that tap sand and gravel, and the wells are capable of yielding 1,000 gallons per minute or more. Stallion Range Center, a military installation on the White Sands Missile Range, about 15 miles east of =he waterfowl refuge, needs about 100,000 gallons per day of potable water. Potable water in large quantities is not known to be available at a location closer to the Center than the refuge area. The Fish and Wildlife Service, which operates the waterfowl refuge, gave permission to White Sands Missile Range to test drill and to develop a supply well in certain areas along the Rio Grande outside the managed lands of the refuge. The U.S. Geological Survey was then asked by White Sands Missile Range to choose locations for test drilling and to monitor drilling and testing of the wells. Between 1963 and 1967 test wells were drilled and a suitable location for a supply well as found. The well would be about 250 feet deep and would tap a body of potable water that is about 100 feet in thickness and is thought to underlie an area of at least 5 square miles. This report contains diagrammatic sections that show the lateral and vertical relation of waters of different quality along the Rio Grande in a part of the Bosque del Apache Grant. Basic data are given in tables; they include records of 7 test wells and 12 high-yield supply wells, and 52 chemical analyses of ground water from the wells.

Open-File Report↗
USGS1975

Hydrocarbon potential, geologic hazards, and the technology, time-frame and infrastructure for exploration and development of the lower Cook Inlet, Alaska; a preliminary assessment

The Lower Cook Inlet Outer Continental Shelf (OCS) contains 5600 km 2 of submerged land in less than 200 m of water 150 to 350 km southwest of Anchorage, Alaska. This area could contain from 0.3 to 1.4 billion barrels of oil and from 0.6 to 2.7 trillion cubic feet of natural gas depending upon the statistical confidence level indicated. The known geology of this submerged area, is extrapolated to the offshore from onshore data. The sedimentary rocks are as old as Triassic and as young as Pleistocene. The Mesozoic strata include volcanic rocks, volcanoclastic and marine clastic sediments. Tertiary, rocks from which the oil and gas in Upper Cook Inlet are produced, consist of nonmarine conglomerate, sandstone, siltstone and coal. The potential objective section for oil and gas in this OCS area ranges from Middle Jurassic through the Tertiary. The present structural configuration of this area is a northeast trending trough filled with Tertiary sediments. The trough is flanked by two major faults, the Bruin Bay fault on the northwest and the Border Ranges fault on the southeast. Between these faults is the OCS area containing anticlinal structures and faults which may be traps for hydrocarbons. Potential geologic hazards are present in this area. It is an area of intense tectonism expressed as seismic activity (earthquakes) and volcanic eruptions which produce many natural disturbances including tsunamis. This distribution of soft sediment and other submarine features which relate to geologic hazards are only generally known.

Alaska↗
USGS1976

Water and stream-sediment sampling techniques for use in uranium exploration

Methods of sampling water and stream sediments for uranium were established in this study. Water samples should be taken using a US DH-48 water sampler across the stream channel and should be filtered and acidified in situ. Stream sediments should be taken as a composite sample up and across the axis of the channel. Only sediment fractions less than 90 ?m (170 mesh) should be analyzed for uranium. The elements As, Ca, Al, B, Mg, K, and Na exhibit a positive correlation with uranium in surface waters, while a much larger suite of elements exhibit a positive correlation with uranium in stream sediments: K, Mn, Mg, Ti, Ca, Al, Fe, Pb, Cr, Y, Zr, Li, Zn, Th, and As. Analyses have revealed that anomalies detected in either the dissolved or suspended fractions of water, or the stream sediments, are frequently not reflected in the other two; hence, all three should be sampled and analyzed.

Open-File Report↗