Named after Horseshoe Bend of Little North Fork. Type section designated as exposures in roadcuts along Little North Fork of Middle Fork of Feather River, secs.1, 12-13 T22N R6E, Pulga 15' quad, Plumas and Butte Cos, CA. Extends into Bucks Lake 15' quad. Consists of metabasalt, meta-andesite, metadacite, metarhyolite, marble, phyllite, quartzite, metachert, and metatuff. These various lithologies shown separately on maps of Pulga and Bucks Lake 15' quads. Is 300 m thick. Presumably overlies Duffey Dome and Franklin Canyon Formations. Underlies Jurassic and Cretaceous ultramafic and plutonic rocks. Age given as Paleozoic(?).
Source: GNU records (USGS DDS-6; Menlo GNULEX).
Horseshoe Bend Formation is considered to be of probable Permian(?) age. Is heterogeneous sequence of interbedded metavolcanic and metasedimentary rocks including thin layers of limestone. Can be divided into: oldest rocks of metabasalt, middle part of phyllite and quartzite, and upper part of basaltic rocks with some quartzite layers.
Source: GNU records (USGS DDS-6; Menlo GNULEX).
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