The eastern (right) side of dumbbell-shaped Lake O'a (Lake Shalla) forms the 17-km-wide O'a caldera. Greenish-colored Lake Kunni (Lake Abiata) at the upper right lies NE of the Pleistocene caldera. Post-caldera activity produced pyroclastic cones north of the caldera. The small greenish Chitu maar on the SW side of the lake was erupted in an area of Holocene vents along the Corbetti-Shalla fissure system extending north from Corbetti caldera. Fumarolic activity continues on the southern and eastern shores of the lake.
NASA/ISS Expedition 1 Crew
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