HR: 1400h
AN: V43A-02    [Abstracts]
TI: Study of Thermal Anomalies at Cotopaxi Volcano, 2002 to 2005
AU: * Rivero, D R
EM: drivero@igepn.edu.ec
AU: Beate, B
EM: bbeate@uio.satnet.net
AU: Troncoso, L
EM: ltroncoso@igepn.edu.ec
AU: Ramón, P
EM: pramon@igepn.edu.ec
class='hr'> AB: The Instituto Geofisico of the Escuela Politecnica Nacional (IG-EPN) has maintained continuous monitoring since 1977, allowing a better understanding of the volcano's baseline activity. Preliminary signs observed since 2001 of a possible reactivation of this volcano after more than a century of repose, prompted a comprehensive seismological study and implementation of new methods of monitoring, based mainly upon a general increase in seismic activity (VT and LP); appearance of new types of seismic signals never observed before (hybrids, "tornillos", big LP, and tremor); an increase in the fumaroles' number and discharge, as well as a marked thermal anomaly in the summit region. Seismic activity reached its peak in late 2001 / early 2002 and was correlated with enhanced degassing from the crater, with vapor columns reaching some meters above the crater level with abundant SO2 perceived. In this abstract we show evidence of the existence of a magmatic intrusion (Troncoso, 2005), that has disturbed the hydrothermal system present in the cone and it is melting the glacier. This has generated local population and civil defense concern. Since this stage of activity, Cotopaxi has not yet returned to its baseline level, therefore the newly implemented technology includes periodic over flights with a FLIR camera, which permits localization and identification of thermal anomalies. Additionally, a telemetric video camera has been deployed in the northwest rim of the crater to identify degassing changes and its relationship with seismic events. Finally, the IG-EPN staff perform continuous visits to the crater to observe changes IN the ice-cap, measure temperatures and verify the presence of magmatic gases.
UR: http:www.igepn.edu.ec
DE: 7280 Volcano seismology (8419)
DE: 8419 Volcano monitoring (7280)
DE: 8485 Remote sensing of volcanoes
SC: Volcanology, Geochemistry, and Petrology [V]
MN: 2007 Joint Assembly