Report on Colima (Mexico) — 30 January-5 February 2002
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 30 January-5 February 2002
Managing Editor: Gari Mayberry
Please cite this report as:
Global Volcanism Program, 2002. Report on Colima (Mexico). In: Mayberry, G (ed.), Weekly Volcanic Activity Report, 30 January-5 February 2002. Smithsonian Institution and US Geological Survey.
19.514°N, 103.62°W; summit elev. 3850 m
All times are local (unless otherwise noted)
The Universidad de Colima reported on 30 January that the growing lava dome at Colima could result in either a dome collapse in days or weeks that would send pyroclastic flows down the volcano's S flank, or explosions could destroy the lava dome and hurl volcanic fragments several kilometers. On 4 February at 1721 a landslide occurred off of the dome, sending material to less than 600 m from the volcano's summit to the S towards Cordobán ravine. Several incandescent landslides were seen traveling less than 1 km down the S and SSW flanks of the volcano. During a flight over the volcano, members of the Advisory Scientific Committee noticed that dome growth occurred towards the W. Seismicity was relatively low; numerous earthquakes with very low magnitudes occurred. The 6.5-km-radius exclusion zone remained in effect, in addition there were restrictions to access within a radius of 11.5-km from the volcano's summit. Residents were advised to be ready in case an increase in activity leads to the evacuation of towns around the volcano.
Geologic Background. The Colima volcanic complex is the most prominent volcanic center of the western Mexican Volcanic Belt. It consists of two southward-younging volcanoes, Nevado de Colima (the 4320 m high point of the complex) on the north and the 3850-m-high historically active Volcán de Colima at the south. A group of cinder cones of late-Pleistocene age is located on the floor of the Colima graben west and east of the Colima complex. Volcán de Colima (also known as Volcán Fuego) is a youthful stratovolcano constructed within a 5-km-wide caldera, breached to the south, that has been the source of large debris avalanches. Major slope failures have occurred repeatedly from both the Nevado and Colima cones, and have produced a thick apron of debris-avalanche deposits on three sides of the complex. Frequent historical eruptions date back to the 16th century. Occasional major explosive eruptions (most recently in 1913) have destroyed the summit and left a deep, steep-sided crater that was slowly refilled and then overtopped by lava dome growth.