A Brief Guide to the Parapet View, Sinnott Memorial, Crater Lake National Park by John Campbell Merriam, 1938
View 1: This mountain is Part of a Tremendous Series of Lava Flows
Numerous volcanoes in this lava region represent relatively late outpourings of melted rock through small openings. They have contributed only an extremely small part to the total mass of lava. The mountain at Crater Lake is one of these volcanoes.In late geological ages enormous flows of molten rock poured out over an area of more than 200,000 square miles, extending into Oregon, Washington, Montana, Idaho, Nevada, and California. These masses of lava came to the surface largely through great fissures in the earth. A typical section of such extensive flows is shown in the lava beds forming Columbia River Gorge.
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