Chaitén is a small volcano locate on the flank of the Michinmahuida volcano in southerly Chile. It is rigid on the West coast of South America about 150km east of the Peru Chile Trench. At this margin, clearly marked on the map and cross section opposite, there is oceanic to Continental convergence. This is a destructive margin, where the boringr Nazca menage is subducted beneath the less dense continental lithosphere of the South American plate. As the plate descends it sources earthquakes in the Benioff zone, and volcanoes occur here because of melting of the plate in the asthenosphere. These are the causes of this volcano, which is explosive because the lava is Rhyolitic, has luxuriously gas pressure and spirited Silica content. Chaitén is also part of the worlds longest fold mountain chain, the Andes Mountains, which are crumpled up be the tectonic forces pushing these 2 plates together. In this southern part of the subduction zone the oceanic plate dips at a steep angle, while the northerly end may be experiencing flat-slab subduction (in which the oceanic slab slides beneath the continental plate at a very low angle).
This low angle of subduction may apologise the relative lack of volcanic activity in the northern part of Chile, compared to the extremely active southern volcanic mountains, which was the cause of the Chaitén eruption.
This volcano has a history of eruptions but in human terms it is infrequent. Before 2008, it consisted mainly of a rhyolitic lava noggin that was last active 9,400 years ago. This is very low frequence! In May 2008, Chaitén began erupting violently, producing numerous plumes, pyroclastic flows, minor earthquakes and lahars, and grammatical construction a new lava dome on the north gradient of the old one. The ash cloud was up to 17 kilometres high and was visible on satellite images for hundreds of kilometres over the Atlantic. A interchange spine of lava was pushed out of the new dome, but will presumable collapse; as such features are...If you want to get a full essay, order it on our website: Orderessay
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