Some regularity in the process of re-awakening of andesite and dacite volcanoes: specific features of the 1982 El Chichon volcano, Mexico reactivation
Por:
Zobin V.M., Jiménez Z.
Publicada:
20 ago 2008
Resumen:
El Chichon volcano is an andesite stratovolcano in southern Mexico. It erupted in March 1982, after about 550 years of quiescence. The 1982 eruption of El Chichon has not been followed by the growth of a lava dome within the newly formed crater. This is rather anomalous since the construction of a new dome after the destruction of an old one is a common process during the eruptions at andesite and dacite volcanoes. To discuss this anomalous aspect of the El Chichon eruption, some regularity in the process of re-awakening of dormant (here defined as a period of quiescence of more than 100 years) andesite and dacite volcanoes are studied based on the seismic activity recorded at the volcanoes Bezymianny, Mount St. Helens, El Chichon, Unzen, Pinatubo and Soufriere Hills. Three stages were identified in the re-awakening activity of these volcanoes: (1) preliminary seismic activity, leading up to the first phreatic explosion; (2) activity between the first and the largest explosions; (3) po
Filiaciones:
Zobin V.M.:
Observatorio Vulcanológico, Universidad de Colima, Colima, 28045, Mexico
Jiménez Z.:
Univ Nacl Autonoma Mexico, Inst Geofis, Mexico City 04510, DF, Mexico
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