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Photogeologic map showing distribution of sinkholes south of Fairplay, Park County, Colorado — A possible geologic hazard Photogeologic map showing distribution of sinkholes south of Fairplay, Park County, Colorado — A possible geologic hazard
A large group of at least 50, and perhaps significantly more, sinkholes partially surrounds Black Mountain 6-10 mi south Fairplay in South Park, Park County, Colorado. The sinkholes occur in bedrock in the evaporite facies of the Middle Pennsylvania Minturn Formation, and in Quaternary soil, alluvium, and glacial outwash gravels that overlie the evaporite beds. Sinkholes range in size...
Geologic map of Port Moller, Stepovak Bay, and Simeonof Island quadrangles, Alaska Peninsula, Alaska Geologic map of Port Moller, Stepovak Bay, and Simeonof Island quadrangles, Alaska Peninsula, Alaska
Geologic mapping of Port Moller, Stevopak Bay, and Simeonof Island 1° by 2° quadrangles on the Alaska Peninsula was conducted as part of the Alaska Mineral Resource Assessment Program (AMRAP). Geologic observations was obtained by using helicopter overflights, vertical aerial photography, and enhanced and extensively processed Landsat imagery (York and others, 1984; Wilson and York, 1985...