Geological History of Crater Lake National Park

FIG. 13—GEOLOGICAL RECONNOISSANCE MAP OF CRATER LAKE.
G. Glacial moraine and dacite tuff. D¹. Tuffaceous dacite. D. Dacite. B. Basalt. A. Hypersthene-andesite. —a. Hypersthene-andesite dikes. —d. Dacite dikes. —>. Glacial striae.
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