The explosion of a volcanic cone followed by the cone's collapse creates this bowl-shaped crater
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Depressions such as Crater Lake, formed by collapse of volcanoes, are... [DOC] [TLE] volcanic cone - National Geographic Society [PAR] Oct 31, 2014 ... A volcanic cone is the triangle-shaped hill formed as material from volcanic ... 
Mount Mazama was a composite cone volcano that collapsed about 7,700 years 
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