Edwards Slough Diorite.  Name proposed for unit in /Horseshoe Basin magma series [informal] (new).  Mapped in secs. 33 and 34, T. 40 N., R. 25 E., Toats Coulee Creek region, Okanogan Range, Okanogan County, Washington.  Is a dark-bluish gray, chiefly fine-grained diorite.  Age is Early to medial Cretaceous.
Type area stated to be in secs. 33 and 34, T. 40 N., R. 25 E., Okanogan Co., WA.
["Horseshoe Basin magma series" considered informal.  Term "Series" is applied formally only to chronostratigraphic units (ACSN, 1961, 1970; NACSN, 1983, 2005, 2021).  US geologic names lexicon (USGS Bull. 1520, p. 92) lists Edwards Slough Diorite of Horseshoe Basin Group (explanation not given).]
Source: GNU records (USGS DDS-6; Menlo GNULEX); US geologic names lexicon (USGS Bull. 1520, p. 92).
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
Asterisk (*) indicates published by U.S. Geological Survey authors.
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