Geology topics
Avery A. Drake
Publications and source records attributed to Avery A. Drake.
Reply. Melanges and the Piney Branch complex - a metamorphosed fragment of the central Appalachian ophiolite in northern Virginia.
Several points in the original paper are clarified. (Preceding abstract)-M.S.
The Piney Branch Complex: A metamorphosed fragment of the central Appalachian ophiolite in northern Virginia
No abstract available.
Bedrock map of Fairfax County, Virginia
The generalized rock-type of lithologic map separates the firm consolidated bedrock that underlies most of Fairfax County into thirteen (13) major rock types; each type groups rock units with grossly similar physical characteristics. Although crystalline bedrock underlies the Coastal Plain deposits of Eastern Fairfax County, it was not subdivided on this map. The only available information is based on interpretations from a few widely scattered deep drill holes and aeromagnetic and gravity surveys. Three sedimentary and ten (10) crystalline rocks on the Explanation are arranged in order from softest, best bedded, most foliated and readily splittable - to hardest, most massive, and least readily splittable.
Geologic map and sections of parts of the Portland and Belvidere quadrangles, New Jersey-Pennsylvania
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Preliminary log of exploratory hole drilled near Riegelsville, Pennsylvania
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Economic geology of the Central City district, Gilpin County, Colorado
The Central City district, in Gilpin County, Colo., is on the east flank of the Front Range, about 30 miles west of Denver. The district is the most important mining camp in the Front Range mineral belt, and has yielded more than $100 million worth of gold, silver, uranium, and base-metal ores since 1859. Gold accounts for about 85 percent of the dollar value of the ore. In recent years mining activity has been slack but from 1950 to 1955 the search for uranium ores stimulated prospecting and development.
Preliminary geologic report on the 1961 U.S. expedition to Bellingshausen Sea, Antarctica
Five areas of outcrop were examined along 120 miles of the coast of the Bellingshausen Sea east of the Thurston Peninsula. Hornblende quartz diorite is the principal rock in the area and occurs in a body of batholithic dimensions. The quartz diorite contains inclusions of older granulitic rock and is cut by mafic dikes. An island in Paradise Harbor on the Palmer Peninsula was also examined briefly.