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Clyde Wahrhaftig

Publications and source records attributed to Clyde Wahrhaftig.

29 records · Page 2Linked to original sources
USGS1960

The physiographic provinces of Alaska

The wealth of recently accumulated geographic information on Alaska has made desirable a new classification of the state into physiographic divisions. Most of Alaska is now covered by topographic maps of high quality at scales of 1:63,360 and 1:250,000, prepared by multiplex methods from aerial photography. A classification made now is not likely to err through lack of knowledge of the geography and topography of the state; any changes it requires will reflect matters of judgment and taste, rather than ignorance. The accompanying classification was prepared intermittently between 1949 and 1959; most of the work was done between 1956 and 1959. It is hoped that it will bring about a clearer understanding of the geography of Alaska and will stimulate research into the history of development of Alaskan landforms.

Alaska↗
USGS1954

Stripping-coal deposits on lower Lignite Creek, Nenana coal field, Alaska

Stripping-coal reserves in an area of about 9.4 square miles extending from the Nenana River about 6 miles up the valley of Lignite Creek are estimated to amount to about 95, 000, 000 tons. The stripping-coal reserves are located in the lower and middle members of the Tertiary coal-bearing formation. Five continuous beds in the middle member range in thickness from 5 to 30 feet, and a discontinuous bed at the base of the lower member is about 60 feet thick. Analyses of outcrop samples, as received at the laboratory, show a heating content of 7,500--8,200 Btu, an ash content of 6 to 14 percent, and a moisture content of 25 percent. The reserve estimate is based on a maximum thickness of overburden of 200 feet. Coal below the level of Lignite Creek or its major tributaries was not considered as it was assumed that stripping would be by hydraulic methods. Uncertainties regarding the position of the coal outcrops and the extent of burning of the coal beds are the basis for a recommendation that, where possible, the stripping reserves be tested by drilling. Overburden consists largely of weakly consolidated sandstone and includes some coarse gravel and a few boulders 20 feet or more in diameter. Water for hydraulic mining can be obtained from the Nenana River. Lignite Creek does not appear to be a dependable source. Disposal of debris may affect the channel of the Nenana River causing damage to railroads and structures. Landslides are common in the valley of Lignite Creek and will affect mining operations and transportation routes.

Circular↗
USGS1953

Quaternary geology of the Nenana River and adjacent parts of the Alaska Range, Alaska

The Nenana River flows northward across the Alaska Range near 149° west longitude. Sedimentary bedrock formations of its basin include pre-Cambrian schist undifferentiated Paleozoic and Mesozoic rocks, continental upper Cretaceous rocks and poorly consolidated continental Tertiary rocks. Igneous rocks include pre Devonian quartz orthoclase schist, greenstone, granitic and basic intrusives of pre- Upper Cretaceous age, and doleritic and andesitic intrusives of Upper Cretaceous age.

Alaska↗
USGS1953

Geology and coal deposits of Jarvis Creek coalfield, Alaska

The Jarvis Creek coal field lies on the north side of the Alaska Range between latitudes 63 ° 35' and 63 ° 45 N., and longitudes 145 ° 40' and 145 ° 50 W. It is 2 to 6 miles east of the Richardson Highway. The coal field is about 16 square miles in area, the major part of which is a rolling plateau that slopes gently northward and is bounded on the east, south and west, by bluffs facing Jarvis Creek, Ruby Creek and Delta River. The oldest rock is pre-Cambrian Birch Creek schist, which is largely quartz-sericite schist with many quartz veins, and is locally intruded by rhyolite dikes. it is overlain by the Tertiary coal-bearing formation. Quaternary deposits include gravel, till, solifluction debris, and wind-borne deposits.

Alaska↗