Global Volcanism Program | Image GVP-00694
Merapi volcano, one of Indonesia's most active, rises above the city of Yogyakarta in central Java. This May 1987 view from the southern flank with the red-roofed Plawangan observatory on the forested ridge in the foreground shows Merapi's degassing summit lava dome. Unvegetated areas on the left result from periodic rockfalls, avalanches, and pyroclastic flows (block-and-ash flows) from the growing lava dome.
Photo by Tom Casadevall, 1986 (U.S. Geological Survey).