During the last week, the total seismic activity of the volcano Cotopaxi showed a slight decrease compared to previous weeks. Seismicity is characterized by the sporadic presence of seismic signals related to emissions, called tremor of emission and the generation of volcano tectonic earthquakes (VT), who came to present an average of 40-50 events / day. The magnitude of VTs events is generally less than 1, but it was recorded a magnitude 2.7 on October 14.
As in previous weeks the energy associated with the activity has not increased significantly in recent weeks and slightly remains above background levels. It also produces small occasional explosions.
The station of the inclinometer VC1 (northeast side) continues on the same trend that has taken place over the last month, coinciding with the decline of earthquakes, especially the VT type. The extent of the deformation composed, recorded by the station remains stable during this period. In general, the deformation is lower than in previous months. The deformation level is still low, compared to deformation patterns recorded on other volcanoes.
Dated on October 17, the maximum values ranged from 450 to 6600 tons / day.
Last ash fall was reported by spotters and published in our report of 19 October. It was reported that there were slight falls in the sectors of Aloasi, Aloag, Jambelí El Chaupi and Tanicuchi, and especially in a region North-east and west of the volcano. Subsequently, during the clear nights of 25 and 26, using a thermal camera IGEPN, it was observed a certain level of brightness of the crater, which is the result of radiation reflection in the gases leaving the crater.
The ashes were re-collected October 20 include those of the ash fall from the beginning of the month and have a high concentration of microlites and dense components, as well as free crystals. There is little presence of vesicular fragments (type slag or pumice) that could be considered as a sign of juvenile magma.
October 30, 2015. Cotopaxi, Equateur :
Source : IGEPN
Photo : Cotopaxi volcano