Mount Merapi, a volcano in central Java considered to be one of Indonesia's most active, underwent a brief outburst of volcanic activity between 1.12 and 1.16 pm local time (6.12 and 6.16 am GMT) on Thursday 27 March 2014, during which it generated a number of small Earthquakes, as well as emitting volcanic gas and ejecting ash and gravel from its crater. The events have caused some concern locally, and been related to an Earthquake that occurred in the same region on Monday 24 March.
Mount Merapi on Thursday 27 March 2014. Balai Penyelidikan dan Pengembangan Teknologi Kebencanaan Geologi.
Mount Merapi lies in a densely populated area of Java, on the borders of Central Java and Yogyakarta Provinces, only 28 km to the north of Yogyakarta city. It has been erupting more-or-less continuously since 1548, and has been responsible for numerous fatalities, most recently in 1994 when a pyroclastic flow (avalanche of hot gas and ash) killed 27 people, mostly in the town of Muntilan, to the west of the volcano. Since then Merapi has undergone tow major eruptive episodes, in 2006 and 2010, without any further loss of life, largely due to prompt evacuations by Indonesian authorities.
The Indo-Australian Plate, which underlies the Indian Ocean to the south of Java, is being subducted beneath the Sunda Plate, a breakaway part of the Eurasian Plate which underlies Java and neighbouring Sumatra, along the Sunda Trench, passing under Java, where friction between the two plates can cause Earthquakes. As the Indo-Australian Plate sinks further into the Earth it is partially melted and some of the melted material rises through the overlying Sunda Plate as magma, fuelling the volcanoes of Java and Sumatra.
See also Eruptions on Tankubanparahu, West Java, Activity in the Tengeer Caldera, Large Earthquake to the south of East Java and Seismic activity beneath Mount Tangkubanparahu.
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