Maipo volcano, seen here from the west, partially fills the Pleistocene Diamante caldera. The floor of the large 15 x 20 km caldera, which formed about 0.45 million years ago during an eruption that produced a 450 cu km ignimbrite, is visible below Maipo. The 5264-m-high basaltic-andesite stratovolcano has a relatively simple structure, but has a flank rhyodacitic lava-dome complex and pyroclastic cones on its eastern flank. Lava flows from these cones extend into Laguna Diamante on the eastern side of the caldera. Photo by Wolfgang Foerster, courtesy of Oscar González-Ferrán (University of Chile).