The Mexican National Centre for Disaster Prevention has reported a sharp increase in volcanic activity on Mount Popocatépetl, the country's second highest volcano, this weekend. The activity began with a series of Earthquakes beneath the volcano on Friday 3 November 2017, (most large eruptions are preceded by Earth tremors, as magma moves into chambers beneath the volcano), followed by about 200 minor eruptions and then three larger, explosive eruptions, beginning after 6.00 am local time on Saturday 4 November, large enough to cause ashfall in nearby communities and prompt the Washington Volcanic Ash Advisory Center to issue a warning to aviation.
Ash emmisions from Mount Popocatépetl on 4 November 2017. Webcams de México.
Popocatépetl has been more or less constantly erupting since the mid 1990s, but most of the time this activity remains at a low level. Major eruptions on Popocatépetl are a cause for concern as the volcano is in a densely populated area, with 30 million people living within the potential hazard zone. The last major eruption, a Plinian (or Vesuvian) event in about 800 AD, triggered a series of pyroclastic flows and lahars that scoured the basins around the volcano.
The location of Popocatépetl. Google Maps.
The volcanoes of the Trans-Mexican Volcanic Belt (including Popocatépetl) are fuelled by the subduction of the Cocos Plate beneath the North American Plate along the Middle American Trench to the south of Mexico. As the subducting plate sinks into the Earth it is melted by the heat and pressure, and volatile minerals liquefy and rise through the overlying North American Plate as magma, fuelling Mexico's volcanoes.
The subduction of the Cocos Plate beneath the North American Plate in Mexico, and how it leads to volcanoes and Earthquakes. King Saud University.
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