"Dallol is a volcanic explosion crater (or maar) in the Danakil Depression, northeast of the Erta Ale Range in Ethiopia. It has been formed by the intrusion of basaltic magma in Miocene salt deposits and subsequent hydrothermal activity. Phreatic eruptions take place here, the last known one in 1926, numerous other eruption craters dot the salt flats nearby. These craters are the lowest known subaerial volcanic vents in the world, at over 45 m (150 ft) below sea level." Wikipedia
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