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At least 559 records · Page 31Linked to original sources
USGS2013

An exploration in mineral supply chain mapping using tantalum as an example

This report uses the supply chain of tantalum (Ta) to investigate the complexity of mineral and metal supply chains in general and show how they can be mapped. A supply chain is made up of all the manufacturers, suppliers, information networks, and so forth, that provide the materials and parts that go into making up a final product. The mineral portion of the supply chain begins with mineral material in the ground (the ore deposit); extends through a series of processes that include mining, beneficiation, processing (smelting and refining), semimanufacture, and manufacture; and continues through transformation of the mineral ore into concentrates, refined mineral commodities, intermediate forms (such as metals and alloys), component parts, and, finally, complex products. This study analyses the supply chain of tantalum beginning with minerals in the ground to many of the final goods that contain tantalum.

Open-File Report↗
USGS2014

Coalbed natural gas exploration, drilling activities, and geologic test results, 2007-2010

The U.S. Geological Survey, in partnership with the U.S. Bureau of Land Management, the North Slope Borough, and the Arctic Slope Regional Corporation conducted a four-year study designed to identify, define, and delineate a shallow coalbed natural gas (CBNG) resource with the potential to provide locally produced, affordable power to the community of Wainwright, Alaska. From 2007 through 2010, drilling and testing activities conducted at three sites in or near Wainwright, identified and evaluated an approximately 7.5-ft-thick, laterally continuous coalbed that contained significant quantities of CBNG. This coalbed, subsequently named the Wainwright coalbed, was penetrated at depths ranging from 1,167 ft to 1,300 ft below land surface. Core samples were collected from the Wainwright coalbed at all three drill locations and desorbed-gas measurements were taken from seventeen 1-ft-thick sections of the core. These measurements indicate that the Wainwright coalbed contains enough CBNG to serve as a long-term energy supply for the community. Although attempts to produce viable quantities of CBNG from the Wainwright coalbed proved unsuccessful, it seems likely that with proper well-field design and by utilizing currently available drilling and reservoir stimulation techniques, this CBNG resource could be developed as a long-term economically viable energy source for Wainwright.

Alaska↗
USGS2014

Events affecting gold exploration in Venezuela since 1999

The structure of the gold mining industry in Venezuela has changed significantly since 1999 as a result of Government policy changes and industry response to these changes. This report documents the policy decisions that have affected the mining industry, discusses the response of the industry on a site by site basis, and suggests possible effects of these changes on the global economy. For the short term, at least, it appears that these changes have made Venezuela a more difficult place to invest for U.S. and Canadian companies, while investment by Chinese entities has been encouraged.

Open-File Report↗
USGS1964

Suggested exploration target in west-central Maine

Reconnaissance geochemical drainage surveys have located a stream in the southern part of the Long Pond quadrangle in Somerset County, Maine, where the active stream sediment contains as much as 2,500 parts per million (ppm) lead and 7,000 ppm zinc. Although this anomaly has been known for some time, its apparent significance has recently increased. Reappraisal of the anomalous pattern in the light of a large quantity of geochemical data obtained by a regional geochemical mapping program during the past two years has shown that this lead anomaly is by far the strongest one yet found by the Geological Survey in Maine. Galena-and pyrite-bearing quartz veins are present in the drainage basin of this stream, but the exposed veins are not believed to contain enough lead to be the principal cause of the geochemical anomaly. Accordingly, the drainage basin of this stream is believed to be above average in mineral potential. The anomalous stream, here named Pyrite Creek for convenience, is the northeastern branch of a major tributary to Bean Brook. Figure 1 presents the data of the detailed geochemical survey along Pyrite Creek, reconnaissance geochemical data in the surrounding area, and the approximate distribution of the major rock types.

Maine↗
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↗