Wednesday 20 April 2016

Eruption on Mount Popocatépetl.

Mount Popocatépetl in southern Mexico underwent a major eruption on Monday 18 April 2016, producing a column of ash rising 3 km above the summit and throwing incandescent material (glowing hot rocks and ash) over 1.6 km from the volcano's crater. The eruption, which began at about 2.30 am local time, is the first major eruption on the Mount Popocatépetl since Sunday 3 April (Popocatépetl has been more or less constantly erupting since the mid 1990s, but most of the time this activity remains at a low level), and happened with relatively little warning (most large eruptions are preceded by Earth tremors, as magma moves into chambers beneath the volcano).  Ash from the eruption drifted to the southeast, with a number of towns and cities in the area reporting ashfalls, and Puebla International Airport was forced to close temporarily due to the hazards presented by the ash.

Erption on Mount Popocatépetl on Monday 18 April 2016. Webcams de México.

Volcanic ash is extremely hazardous to aircraft in a number of ways. At its most obvious it is opaque, both visually and to radar. Then it is abrasive, ash particles physically scour aircraft, damaging components and frosting windows. However the ash is most dangerous when it is sucked into jet engines, here the high temperatures can melt the tiny silica particles, forming volcanic glass which then clogs engine. When this happens the only hope the aircraft has is to dive sharply, in the hope that cold air passing through the engine during the descent will cause the glass to shatter, allowing the engine to be restarted.

 The location of Popocatépetl. Google Maps.

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 subduction of the Cocos Plate beneath the North American Plate in Mexico, and how it leads to volcanoes and Earthquakes.

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. 

See also... cancelled after eruption on Mount Colima.                                                     Several flights from airports in Mexico have been cancelled following an eruption on Mount Colima on Wednesday 18 November 2015. The eruption... on Mount Popocatépetl.                The Mexican National Centre for Disaster Prevention reported a series of eruptions on Mount Popocatépetl on Tuesday 20 October 2015, beginning at about 2.00 pm local time, the largest of which produced an ash column which rose 2.5 km over the summit of... on Volcán de Colima.               Volcán de Colima, an active stratovolcano (cone-shaped volcano made up of layers of ash and lava) on the border between Jalisco and Colima States in Mexico, began a series of eruptions in the first week of July 2015, with ash plumes rising as much as 3 km...
Follow Sciency Thoughts on Facebook.