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A fascinating cross section of a hornito was revealed recently, whe...

Detailed Description

A fascinating cross section of a hornito was revealed recently, when a partial collapse provided a window into a portion of an abandoned lava tube. The void space behind the geologist was filled with lava at some point, with lava and gas forced through the narrow crack in the center of the photograph. This ejected bits of spatter, which solidified around the opening and built a tall hornito.