Growth And Evolution Of A Scoria Cone And Dome Inside The Reventador Volcano Crater.

Abstract:

Reventador volcano is one of the most active volcanoes in Ecuador and is responsible for the strongest eruption in the last 150 years (VEI= 4) in 2002. Since then Reventador is continuously monitored by the Geophysical Institute (IG) including seismic, geodetic and, thermal instrumentation and also visual and satellite observations. Infrared and digital images are regularly obtained during flights over the volcano, which helps to define and understand the activity of Reventador and to describe the different emitted volcanic products since 2002. After the onset of the 2002 eruption, Reventador have had a continuous seismic and superficial activity characterized by explosive and effusive phases, separated in four main eruptive periods. As a result of this activity 17 different lava flows were emitted from the vent to the northern and southern flanks of the cone and deposited inside the caldera during a period of seven years. Since then the surface activity experimented an important change in 2009, turning from an effusive phase to an almost exclusive explosive phase, forming in this way a scoria cone over the vent. This cone of some 130 m in diameter is filling the crater left by the 2002 eruption. Another consequence of this explosive phase was the occurrence of small pyroclastic flows descending less than 100 m from the crater rim. The character of the seismic activity changed again at the end of 2010, evolving from a less explosive phase to a mainly effusive one, associated with the emission of lava flows. In spite of the fact that no lava flows were observed down the flanks of the cone, however a little dome was seen growing inside the crater. This …

Año de publicación:

2012

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