The 1883 eruption of the volcano on the island of Krakatoa was the result of pressure that built up due to two underlying tectonic plates, one being pulled underneath the other. The eruption produced the loudest sound ever recorded and resulted in approximately 36,000 deaths.
The driving force behind the eruption of Krakatoa was the subduction of the Indo-Australian tectonic plate as it moved northward toward Asia. The eruption of Krakatoa was the largest natural disaster of the 19th century and resulted in widespread weather changes that were felt around the world. The force of the eruption was 10,000 times greater than that of the atomic bomb dropped on Hiroshima.
During the eruption of Krakatoa, the magma chamber of the volcano suffered a rupture due to the initial explosion. This rupture, know as a phreatomagmatic event, allowed sea water to come into contact with lava, which created vast clouds of superheated steam that carried pyroclastic flows up to 24 miles at speeds greater than 62 mph. While it is possible that it was a build-up of trapped steam that resulted in such a violent eruption, another theory suggests that the eruption was due to large portions of the volcano collapsing under its own internal pressure.