The Orphan Lode Mine, Grand Canyon, Arizona; a case history of a mineralized, collapse-breccia pipe
1986; United States Department of the Interior; Linguagem: Inglês
10.3133/ofr86510
ISSN2332-4899
Autores Tópico(s)Archaeology and Natural History
ResumoThe Orphan is a single, patented lode mining claim within Grand Canyon National Park.The claim was located for copper in 1893, on the escarpment below Maricopa Point on the south rim.Three short adits were driven in mineralized outcrops near the north end line of the claim and a few sacks of copper ore were reportedly brought out of the canyon.It was patented in 1906 before the surrounding area was protected by Federal law.Uranium was noted in the old workings by the USGS in 1951.The claim was leased in 1953 for uranium exploration, and initial drilling in the old adit (0 level) determined that the ore-bearing structure was a pipe.On the basis of favorable geology and high grade uranium values (greater than 1.00 percent U~08 ) penetrated in a few drill holes, an aerial tram was constructed and production from the Orphan Lode Mine commenced in April 1956.Early ore production was about 1,000 tons-per-month averaging 1.00 percent U3 0Q .Continued exploration indicated that ore continued downward to at least the 400 level, and that a large ore body was present off the claim within the National Park.A 1,500 foot deep shaft from the rim of the canyon and a 1,200 foot crosscut to the 400 level of the pipe, completed in 1959, replaced the aerial tram, and production from the Orphan Lode greatly increased.
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