Geology and Minerals
Dallol is a terrestrial hydrothermal system around a cinder cone volcano in the Danakil Depression, northeast of the Erta Ale Range in Ethiopia. It is known for its unearthly colors and mineral patterns, and the very acidic fluids, commonly noted as some of the most acidic on Earth, that discharge from its hydrothermal springs.
Hill-Annex Mine State Park.
History of the Grand Canyon area.
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