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E. R. King

Publications and source records attributed to E. R. King.

At least 19 recordsLinked to original sources
USGS1990

Precambrian terrane of north-central Wisconsin: an aeromagnetic perspective

A shaded relief magnetic map covering most of the region of exposed Precambrian rocks of north-central Wisconsin shows the structural grain and many lithologic units with clarity and comprehensive detail. The area includes part of the volcanic sequence of the Keweenawan Supergroup south of Lake Superior, the southern margin of the Archean Superior Province, the accreted island-arc terranes of the Penokean Orogen, and the Wolf River batholith. Numerous dikes are evident in the shaded relief, some being more than 200 km in length. Many of the longer dikes are reversely magnetized Keweenawan diabase associated with early extension of the Midcontinent Rift; some apparently were intruded along preexisting faults. A northwest system of dikes and faults indicated by the shaded relief map may be related to later stages of Keweenawan rifting. The Wolf River batholith is characterized by low magnetic relief associated with the predominant granitoids but includes circular plutons of highly magnetic anorthosite and a large area of magnetic rock having a signature different from the mapped anorthosite bodies. A fault bounding the western side of the batholith is paralleled by an apparent system of faults or dikes in the older terrane to the west. The magnetic map covering the Wisconsin magmatic terranes and the Archean Superior Province margin to the north is dominated by east-northeast-trending Penokean rocks. Large units of magnetic mafic rocks and less magnetic granitoid rocks are cut by a system of well-defined northeast shear zones and a more easterly trending, possibly younger set of faults, some of which contain dikes along parts of their lengths. Although the sutures bounding the magmatic terranes generally follow the magnetic trends, they do not have distinctive magnetic signatures.

Wisconsin↗
USGS1986

Precambrian basement geology of North and South Dakota

Combined analysis of drill-hole, gravity, and magnetic data indicates that the buried Precambrian basement rocks of the Dakotas can be divided into several lithotectonic terranes. Eastern North Dakota and northeastern South Dakota are underlain by Archean gneiss. Except for the Black Hills region of South Dakota, where Archean rocks are also exposed, the western third of both Dakotas is underlain mainly by Early Proterozoic gneiss and metasedimentary rocks. Part of this region is underlain by Archean crust with an Early Proterozoic tectonic overprint. A broad transition zone of strongly overprinted Archean crust occurs between the Proterozoic rocks to the west and the Archean rocks to the east. South central South Dakota is underlain by an Early Proterozoic batholith. Early Proterozoic felsic volcanic rocks occur in southeast South Dakota. The bootheel portion of South Dakota contains a diverse assemblage of basement rocks that are partly Archean in age.Churchill Province rocks of the Trans-Hudson foldbelt project into the western Dakotas. The Thompson nickel belt and the Pickwitonei gneiss belt correlate with the western and eastern halves, respectively, of the transition between Archean and Proterozoic crust, and the Archean Glennie – Hanson Lake microcontinent of the Churchill Province likely extends into western North Dakota. Archean rocks of Minnesota extend into the eastern Dakotas, and the Wyoming craton extends to the Black Hills region. The Cheyenne foldbelt projects into southwest South Dakota. The Penokean foldbelt of Michigan and Wisconsin does not extend into the Dakotas, but it most likely extends into northwest Iowa.Tectonic evolution of the Early Proterozoic terrane in the Dakotas was most likely similar to plate tectonic models for the evolution of the Trans-Hudson foldbelt in the Churchill Province. As in the Churchill Province, the western Dakotas are underlain by Early Proterozoic rocks, but it is not known whether these rocks formed as a result of rifting and subsequent closure of a once extensive Archean crust or as a result of collision of once widely separated blocks of Archean crust.

North Dakota, South Dakota↗
USGS1977

Mineral resource appraisal of the New River Gorge, Fayette, Raleigh, and Summers counties, West Virginia

The New River Gorge study area contains 440 square kilometers of a strikingly scenic part of the Appalachian coal field of southcentral West Virginia in Fayette, Raleigh, and Summers Counties. Coal resources of 66 million tons occur in 12 coal beds in the area of the proposed Wild and Scenic River, and coal resources of 151 million tons are present in 13 coal beds in the larger area of the proposed National Park. Coal is produced at one underground mine and several strip mines in or near the study area. The entire New River Gorge area has a potential for natural gas resources, but gas is being currently produced only in the northern part. Oil, however, is unlikely to be found within or near the study area. The extensive resources of sandstone for construction and high-silica rock and shale for common brick are not considered to be economically important in the Gorge area. Resources of other nonmetallic materials including limestone and fire clay are small or nonexistent. Resources of metallic minerals are not known in the study area.

West Virginia↗
USGS1968

Geologic interpretation of reconnaissance aeromagnetic survey of northeastern Alaska

Aeromagnetic surveys of Naval Petroleum Reserve No. 4 (Woolson and others, 1962) and of a 900-square-mile area near Fairbands (Andreasen and others, 1964) are the only published aeromagnetic reports on northeastern Alaska. Several total intensity aeromagnetic profiles, primarily over the Yukon Flats in the central part of the area shown on figure 1, were obtained by the U.S. Geological Survey in 1954 and 1958 and were released for public inspection in 1960 (Andreasen, 1960a, 1960b). Most of these profiles were flown north and south at a barometric elevation of about 2,500 feet; some were flown north and south at 4,000 to 8,000 feet. All of these north-trending profiles are incorporated in this report. Six northwest-trending profiles parallel to the Yukon River between long. 147° W and 144° W. are not included.

Alaska↗
USGS1966

Magnetic data on the structure of the central Arctic Region

A study of 23,000 miles of total intensity aeromagnetic profiles in the central Arctic has been made by the U. S. Geological Survey and the U. S. Coast and Geodetic Survey. The profiles were flown at 20,000 feet above sea level and cover approximately 1,350,000 square miles of the Arctic Ocean between the North Pole and the North American continent. When the profiles are smoothed to remove crustal anomalies, the resulting contoured values differ from the U. S. Hydrographic Office Chart 1703 N for 1955 corrected to 1951 by as much as 2000 gammas in the northern part of the Arctic Archipelago. A nondipole regional focus east of Greenland has decreased in amplitude but has changed very little in position since 1907.5. There is a profound difference in the magnetic characteristics of the rocks on either side of the underwater Lomonosov Ridge across the Arctic Ocean. In the Eurasian Basin the high-altitude profiles are relatively smooth or show only minor anomalies, but on the North American side of the ridge there is a large area of closely spaced, high-amplitude anomalies which has been designated the Central Magnetic Zone. Although the anomaly trends parallel the Alpha Rise, this zone is far more extensive, including nearly half of the Canadian Basin on one side and probably all the Central Arctic Basin on the other side of the rise. The Lomonosov Ridge is marked by a persistent anomaly of moderate size that indicates the presence of magnetic material in the ridge. Probable block-fault structures along the flanks of the Alpha Rise are associated with blocklike magnetic anomalies of comparable widths. A characteristic magnetic pattern occurs over an area of jagged bottom topography in the Eurasian Basin. A similar magnetic pattern over part of the Lena Trough may indicate another area of jagged topography. The belt of epicenters associated with the Mid-Atlantic Ridge continues through this rugged part of the Eurasian Basin, but the absence of the typical high magnetic anomaly makes it doubtful that the mid-oceanic ridge extends through this part of the Arctic . Magnetic data indicate that the thick sections of sedimentary rocks in the Paleozoic geosynclinal belts of northern Ellesmere Island and northern Greenland continue out under the adjacent continental shelves north of Greenland, west of the Arctic Archipelago, north of the part of Alaska east of Barrow, and under part of the Chukchi Shelf, and that they make up the bulk of the Nansen Swell off Spitsbergen. Thick sedimentary fill is indicated in the magnetically flat areas of the Eurasian Basin next to the Lomonosov Ridge and in the southern part of the Canadian Basin. The magnetic profiles on the Eurasian side of the Lomonosov Ridge closely resemble typical magnetic profiles over both Atlantic and Pacific oceans, where as the profiles of the Central Magnetic Zone on the North American side of the Lomonosov Ridge are completely unlike the oceanic data and show a striking similarity to typical profiles over the Precambrian rocks of the Canadian Shield and its buried equivalent under the Central Stable Region of the United States. Therefore, it is concluded that the Arctic region consists of a probable oceanic area on the Eurasian side and a basin formed by downdropped continental rocks, presumably a Precambrian complex similar to that of the Canadian Shield, on the North American side of the ridge.

Geological Society of America Bulletin↗