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R. L. Detterman

Publications and source records attributed to R. L. Detterman.

At least 19 recordsLinked to original sources
USGS2001

Geologic map of the Arctic Quadrangle, Alaska

Introduction The Arctic quadrangle is well located to shed light on the basic geologic relations of northern Alaska. The rocks represent all of the stratigraphic systems from Cambrian to Cretaceous and all but one of the tectono-stratigraphic subterranes of the Brooks Range, from the autochthonous subterrane in the north to the allochthonous subterranes farther south. Among the distinctive geologic features displayed in the Arctic quadrangle are voluminous volcanic rocks of probable Devonian age, a wide array of Carboniferous carbonate facies in the Lisburne Group (which here extends up into the Middle Pennsylvanian), the southward transition of Upper Devonian (Famennian) clastic facies from fluvial conglomerate to marine sandstone, a full display of Upper Devonian (Frasnian) reef-related strata, and fossiliferous Ordovician rocks in both carbonate and chert terranes. Most of the quadrangle is in the Arctic National Wildlife Refuge (ANWR) and Arctic Wildlife Refuge Wilderness. The quadrangle also includes Arctic Village, the only village in the region and a potential destination or transfer point for visitors to the wildlife refuge.

Alaska↗
USGS1994

Mineral-resource assessments in Alaska; background information to accompany maps and reports about the geology and undiscovered-mineral-resource potential of the Mount Katmai Quadrangle and adjacent parts of the Naknek and Afognak quadrangles, Alaska Peninsula

Geologic and geochemical field studies were carded out from 1983 to 1987 in the Mount Katmai l?x2 ? quadrangle and adjoining region, at the northeast end of the Alaska Peninsula. The region is nearly entirely within Katmai National Park and Preserve and has had almost no mineral production, so prior to this study there were few data by which to assess the mineral potential of the region. This report describes the folio of publications that have resulted from the study: geologic maps, geochemical results, fossil identifications, radiometric rock ages, and an assessment of the undiscovered-mineral-resource potential of the region. The Katmai region is inferred to potentially have three types of undiscovered mineral deposits: porphyry copper (molybdenum), precious-metal vein, and hot-springs gold. These deposit types occur elsewhere on the Alaska Peninsula in similar geologic units. Evidence suggesting their occurrence in the Katmai region is the presence of trace amounts of metals typically associated with these kinds of deposits in bedrock of certain tracts and in sediments of streams draining those tracts. Magma to provide heat, fractures to provide pathways for mineralizing fluids, and altered rock are required by genetic models of these deposit types. Such features do occur in the Katmai tracts. Confirmation of any mineral deposit in the Katmai region requires detailed follow-up sampling and acquisition of subsurface information, which is beyond the scope of this study. However, producing porphyry deposits are unknown elsewhere on the Alaska Peninsula in similar rocks, so if any such deposits occur in the Katmai region, they are likely to be few in number. Conversely, vein deposits are typically small in size so there may be several of such deposits. The properties and thermal history of the sedimentary rocks that could serve as reservoirs for oil or gas are unfavorable in adjacent regions. Thus the potential of the Katmai region for producible quantities of fossil fuels is low. In theory the region has shallow concentrations of geothermal fluids, but specific evidence for their presence is obscured by heavy precipitation and cold young rocks or deposits. Small volumes of coal occur at tidewater sites on the Pacific coast.

Circular↗
USGS1987

Preliminary geologic map of the Mount Katmai Quadrangle and portions of the Afognak and Naknek quadrangles, Alaska

This geologic map is the first in a series of maps dealing with geology and mineral resources of the Mt. Katmai area, Alaska. This map series is the result of the U.S. Geological Survey's Alaska Mineral Resources Assessment Program (AMRAP). Subsequent maps in this series will treat fossils, geochronology, detailed Quaternary deposits (both unconsolidated and volcanic), and mineral resources.

Alaska↗
USGS1981

Maps showing aeromagnetic survey and geologic interpretation of the Chignik and Sutwik Island quadrangles, Alaska

An aeromagnetic survey over part of the Chignik and Sutwik Island quadrangles, on the southern Alaska Peninsula, was flown in 1977 as part of the Alaska mineral resource assessment program (AMRAP). Maps at scales 1:250,000 and 1:63,360 have been released on open-file (U.s. Geological Survey, 1978a, 1978b). This report includes the aeromagnetic map superimposed on the topographic base (sheet 1) and an interpretation map superimposed on the topographic and simplified geologic base (sheet 2). This discussion provides an interpretation of the aeromagnetic data with respect to regional geology, occurrence of ore deposits and prospects, and potential oil and gas resources. The survey was flown along northwest-southeast lines, spaced about 1.6 km apart, at a nominal elevation of about 300 m above the land surface. A proton-precession magnetometer was used for the survey, and the resulting digital data were computer contoured at intervals of 10 and 50 gammas (sheet 1). The International Geomagnetic Reference Field (IGRF) of 1965, updated to 1977, was removed from the total field data.

Alaska↗