The Servicio Nacional de Estudios Territoriales has reported a pair of small eruptions on Mount Chaparrastique, or San Miguel, a 2130 m stratovolcano (cone shaped volcano made up of layers of ash and lava) in east-central El Salvador. The first event occurred slightly after 4.50 pm local time on Sunday 14 January 2018, the second a day later at about 4.15 pm local time on Monday 15 January. Both produced small plumes that rose less than 300 m above the summit of the volcano.
The approximate location of Mount Chaparrastique. Google Maps.
El Salvador, and neighbouring Central American states, lies on the Caribbean Plate. To the south of Central America the Coccos Plate, which underlies an area of the east Pacific, is being subducted beneath the Caribbean Plate along the Middle American Trench. As the plate is subducted it is partially melted by the friction and the heat of the planet's interior, giving rise to liquid magma which rises through the Caribbean Plate to fuel the volcanoes of Central America.
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