Seismic activity that accompanied the effusive and explosive eruptions during the 2004–2005 period at Volcán de Colima, Mexico

摘要: Abstract Volcan de Colima is considered the most active in Mexico. A period of large eruptive activity occurred 2004–2005. It began as a swarm long-period events (LPs) late September 2004, indicating onset growth new lava dome its crater. Subsequently, avalanches incandescent material and pyroclastic flows during approximately 2 months occurred. Then, became more explosive with moderate explosions. Finally, swarms LPs accompanied magma ascent extrusion small domes vulcanian explosions 2005. This was investigated continuous seismic signal study, cross-correlation autoregressive analysis monochromatic LPs. For vast majority explosions, an increase rate energy observed Seismic Spectral Energy Measurement (SSEM) from 1 to 3 Hz, before each event. proportional LPs, probably result emission rate. Applying failure forecasting method (FFM) using SSEM inverse parameter, time estimated when adjusted line reaches null value. We observe systematic delay few hours between real occurrence time. suggests that complex processes than pure damaging plug occur The associated include proportion similar waveforms. They form dozen families which stay whole indicate repetitive sources. Some are only could therefore be used early warning. Monochromatic LP this period, some them just explosion. However, no clear relationship their found.