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Andrew Griscom

Publications and source records attributed to Andrew Griscom.

53 records · Page 3Linked to original sources
USGS1976

Aeromagnetic map of the Tanacross Quadrangle, Alaska

The aeromagnetic map (sheet 1) of the Tanacross quadrangle was prepared in 1971 and subsequently released by the State of Alaska as an open-file map (Alaska Div. Geology and Geophysics, 1973). The data were collected along north-south traverses spaced at 1.6-km intervals and from an altitude of 300 m above the ground. Compilation was originally in the form of 30 by 15-minute quadrangles at a scale of 1:63,500; these quadrangles have been combined and reduced to form the present map at a scale of 1:250,000. Contour interval is 10, 20, 100, or 500 gammas, depending upon the steepness of local gradients in the Earth's magnetic field.

Alaska↗
USGS1975

The Alaskan mineral resource assessment program; background information to accompany folio of geologic and mineral resource maps of the Nabesna Quadrangle, Alaska

The Nabesna quadrangle in south-central Alaska is the first of the l:250,000-scale Alaskan quadrangles to be investigated by an interdisciplinary research team in order to furnish a mineral resource assessment of the State. The assessment of the 17,600-km 2 16,800-mi21 quadrangle is based on field and laboratory investigations of the geology, geochemistry, geophysics, and satellite imagery. The results of the investigations are published as a folio of maps, diagrams, and accompanying discussions. This report provides background information on the investigations and integrates the published components of the resource assessment. A comprehensive bibliography cites both specific and general references to the geology and mineral deposits of the Nabesna quadrangle.

Circular↗
USGS1975

Aeromagnetic map of the Nabesna Quadrangle, Alaska

The aeromagnetic map (sheet 1) of the Nabesna quadrangle was prepared in 1971 and subsequently released by the State of Alaska as an open-file map (Alaska Div. Geol. and Geophysics, 1973). The data were collected along north-south traverses spaced at 1.6 km intervals at an altitude of 330 m (1000 ft) above the ground. Compilation was originally in the form of 30' x 15' quadrangles at a scale of 1:63,360; these quadrangles have been combined and reduced to form the present map at a scale of 1:250,000. Contour interval is 10, 20, 100, or 500 gammas, depending on the local range in the earth's magnetic field.

Alaska↗
USGS1970

A gravity and aeromagnetic survey of the mid-Tertiary sedimentary basin on the south coast of Puerto Rico

During the period November 18, 1963 to December 3, 1963 the U.S. Geological Survey in cooperation with the Commonwealth of Puerto Rico performed a gravity survey of the Tertiary sedimentary basin which is located along the south coast of Puerto Rico in the vicinity of Ponce. The project was initiated at the request of Mr. Carlos Vincenty, Director, Department of Industrial Research, Economic Development Administration of the Commonwealth of Puerto Rico. The purpose of the survey was to obtain information on the configuration arid structure of the basin and if possible, to locate areas which might be favorable for the accumulation of oil or gas. The accompanying index map (fig. 1) shows the survey area together with the outline of the border of the basin.

Puerto Rico↗
USGS1969

Aeromagnetic investigation of crustal structure for a strip across the western United States

This report represents part of a larger study undertaken to interpret the gross features of the earth's crust by aeromagnetic methods. The larger survey covers a 100-mile-wide strip along a great circle arc from Washington, D.C., to San Francisco, California. The area considered extends from about 200 miles east of the Rocky Mountains to 150 miles west of the coast of the Pacific Ocean. Inferences on gross structure and lithology are made from the magnetic patterns and trends shown on the map. At the continental margin, the magnetic data strongly suggest that the oceanic crust becomes much more deeply buried as the continent is approached. A large magnetic anomaly extending northwestward along the center of the Great Valley is probably caused by mafic intrusive rocks.

California, Colorado, Kansas, Nebraska, Nevada, Ut↗