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Allen L. Clark

Publications and source records attributed to Allen L. Clark.

18 recordsLinked to original sources
USGS1970

Analyses of rock and stream-sediment samples from the Sumdum C-4 Quadrangle, Alaska

Analytical data for 31 rock and 33 stream-sediment samples from the Sumdum C-4 , 1:63,360 scale quadrangle are presented in this report, together with a statistical treatment of the data. The samples were collected in 1969 as part of the Heavy Metals Program of the U.S. Geological Survey. The most comprehensive discussion of the geology of the study area is a report by A. F. Buddington and Theodore Chapin (1929). Known metalliferous lodes of the area are described and additional references to specific areas are given by Berg and Cobb (1967). Additional data is given in reports by Herbert and Race (1964) and Alaska Department of Mines (1950). Supplemental publications are being prepared on the general geology and mineral occurrences of the study area.

Alaska↗
USGS1969

Geochemical maps of an area northwest of the Chulitna River, central Alaska Range

An area northwest of the Chulitna River in west-central Alaska Range locally shows local anomalous concentrations of gold, silver, arsenic, copper, zinc, and lead in stream-sediment samples. Most stream sediments showing anomalous concentrations of metals can be correlated with either known or newly discovered deposits or occurrences described in Circular 617.

Alaska↗
USGS1968

Geology of the Golden Zone mine area, Alaska

The Golden Zone mine area, in the upper Chulitna district, is underlain mainly by siltstone and tuff, volcanic conglomerate and breccia, and limestone. These rocks were invaded, probably in the Tertiary, by dikes and a small stock of porphyry. The ore deposits of the area are the Golden Zone breccia pipe, a nearly vertical body about in the center of the porphyry stock, and steeply dipping veins. Most veins strike north to northeast and are commonly only 1-5 feet thick, but locally are as much as 15 feet thick. Both pipe and vein deposits are gold deposits of low to moderate grade that are characterized by abundant arsenopyrite; some contain possibly economic amounts of copper, lead and zinc minerals. Of the deposits of the mine area, only the Golden Zone has been explored to any extent, and both it and some of. the veins deserve further exploration to determine their potential.

Alaska↗