Global Volcanism Program | Image GVP-10425
The eastern (right) side of the darker Lake O'a (Lake Shalla) forms the 17-km-wide O'a caldera. Post-caldera activity produced cones N of the caldera. The small light blue-green Chitu maar on the W side of the lake was erupted in an area of Holocene vents along the Corbetti-Shalla fissure system extending N from Corbetti caldera. Fumarolic activity continues along the S and E shores.
NASA International Space Station image ISS001-363-7, 2001 (http://eol.jsc.nasa.gov/).
This image is made available as a Public Domain Work, but proper attribution is appreciated.