Mount Merapi is an active volcano in Indonesia, on the island of Java near the city of Yogyakarta. The volcano is so active that smoke can be seen coming out of the peak almost every day of the year. Mount Merapi has been erupting regularly since 1548.
Mount Merapi is located in the subduction zone, where the Indo-Australian Plate is going under the Eurasian Plate. Geologists estimate that the volcano started forming 400,000. It was largely built up by basaltic lava flows, but the lava flows have become more viscous in the last 10,000 years or so. With the thicker lava, Merapi has had more explosive eruptions and the formation of lava domes. Merapi has minor eruptions every 2 years or so, and major eruptions every few decades.
Even though it’s an extremely active volcano, thousands of people live on its flanks. Hot gas killed 43 people in 1994, and 13 villages and 1400 people were killed by pyroclastic flows during an eruption in 1930. A series of earthquakes struck Mount Merapi in April/May 2006, the most powerful one on May 27th killed 5,000 people. An eruption on June 14, 2006 spewed out a cloud of volcanic ash that covered a village several kilometers away.
We have also recorded an episode of Astronomy Cast about Earth, as part of our tour through the Solar System – Episode 51: Earth.