Mount Lokon on northern Sulawesi erupted explosively slightly before 8.00 am local time on Wednesday 20 March 2013 (slightly before midnight on 19 March, GMT), throwing a column of ask 2 km into the sky, according to Badan Nasional Penangulanggan Bencana (Indonesia's Disaster Mitigation Agency). The eruption came from the Tomohon crater, which lies on a sadle between the more prominent Lokon and Empung craters, and which has been erupting intermittently since 2011, though this eruption was described as exceptionally loud, shocking local people.
The ash column over Mount Lokon. Viva.
Mount Lokon is on Sulawesi's Northern Peninsula, which forms one end of the Sangihe Volcanic Arc, a string of volcanic islands which runs from Sulawesi to Mindanao Island in the Philippines. The arc is formed as part of the Molucca Plate to the east is subducted beneath the Sangihe Plate to the west. As the Molucca Plate sinks into the Earth, it is partially melted by friction and the heat of the Earth's interior. Some of the melted material then rises through the overlying plate, fueling the volcanoes of the Sangihe Arc.
See also Eruption on Gamalama, Earthquake hits Sulawesi, Eruption on Mount Sirung, Eruptions from the Tompaluan Crater, Lokon-Empung, Sulawesi. December 2011 and Volcanoes on Sciency Thoughts YouTube.
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