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dacite ash-flow tuff, generally blue-green in color with abundant biotite and feldspar crystals basalt dike rhyolitic tuff; this unit appears to consist of from 3 to 6 subunits ranging in composition from dacite to rhyolite dacite ash-flow tuffs, generally gray in color with few biotite and feldspar crystals. Lithic fragments are common basalt dike dacite ash-flow tuffs; this is the same unit as between 2275 and 2580 feet. The bottom part of this unit is composed of soft bentonitic clay. There are no easily visible crystals in this unit rhyolite tuffs with common biotite, feldspar, and quartz crystals. This unit is probably composed of 3 or 4 subunits dacite to rhyodacite tuff, light green, very fine-grained. A few quartz, feldspar, and biotite crystals are present. This unit is partially silicified dacite tuffs and (or) flows, predominantly purple with abundant small altered feldspar crystals. Some gravels and fine-grained green tuffs are interbedded in the upper part of this unit dacite tuff, fine grained, noncrystalline, light green gravel, talus (?), and soil (?), contains both phyllite and volcanic chips phyllite metasediments or metavolcanics, fine-grained, massive, gray-green chips phyllite quartzite and (or) argillite; noncalcareous, fine grained, white to light green to gray in color. This unit contains a small amount of mica schist o o

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