Shown on geologic sketch map of Mt. Tallac roof remnant in Fallen Leaf Lake 15' quad, El Dorado Co, CA. Intrudes Triassic(?) and Jurassic metasedimentary and metavolcanic rocks.
Source: GNU records (USGS DDS-6; Menlo GNULEX).
Composed of hornblende-biotite granodiorite which is exposed over nearly 10 sq mi in south-central part of Fallen Leaf Lake 15' quad, El Dorado Co, CA. Intrudes early gabbro-diorite complex, Pyramid Peak granite and Keiths Dome quartz monzonite. Intruded near southern end by basalt dikes. Shown on map of quad as of Cretaceous age.
Source: GNU records (USGS DDS-6; Menlo GNULEX).
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