p. 1387-1388, pl. 1 (geol. map). Singas formation. Sequence of gray to black phyllite interlayered with minor quartzite beds and bioclastic limestone lenses (fragments of crinoids, pelecypods, and brachiopods). Thickness 4,000 to 7,000 feet. Overlies O'Neill formation (new), contact drawn at top of highest O'Neill quartzite bed. Underlies Andorno formation (new). Fossils (identified by N.J. Silberling, USGS) indicate age is early or middle Late Triassic.
Named from Singas Creek, Santa Rosa Range, Winnemucca region, north-central NV. [Type locality not designated.] Well exposed on ridge between Wash O'Neill Creek [also spelled O'Neal] and Provo Canyon. Composes most all of Bloody Run Hills.
Source: US geologic names lexicon (USGS Bull. 1200, p. 3613); GNU records (USGS DDS-6; Menlo GNULEX).
Included as second youngest formation in Auld Lang Syne Group (new) in south Santa Rosa Range. Type "area" of Compton (1960) redesignated as type locality: secs.26-27 T41N R38E, Paradise Valley 15' quad, Humboldt Co, NV. Underlies Andorno Formation; overlies O'Neill Formation (both of Auld Lang Syne Group). Age is Late Triassic (Norian).
Source: GNU records (USGS DDS-6; Menlo GNULEX).
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
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