This is a view of the El Chichon caldera, formed during the very explosive eruptions of late March and early April of 1982. The caldera is about a kilometer wide and a few hundred meters deep. Prior to the 1982 eruptions the summit of the volcano consisted of a large lava dome within a shallow caldera. There is a shallow acidic lake in the caldera, fed entirely by ground water. You can see that there have been numerous landslides into the caldera.
For more on El Chichon, click here.
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