Report on Colima (Mexico) — 25 May-31 May 2005
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 25 May-31 May 2005
Managing Editor: Gari Mayberry
Please cite this report as:
Global Volcanism Program, 2005. Report on Colima (Mexico). In: Mayberry, G (ed.), Weekly Volcanic Activity Report, 25 May-31 May 2005. Smithsonian Institution and US Geological Survey.
19.514°N, 103.62°W; summit elev. 3850 m
All times are local (unless otherwise noted)
The largest eruption at Colima in the past 20 years occurred on 30 May at 0326. Pyroclastic flows that accompanied the eruption traveled W. Satellite imagery showed a portion of an ash cloud produced during the eruption at a height of ~8.5 km (~27,900 ft) a.s.l. extending SE, and a lower portion of the cloud at ~5.4 km (~17,700 ft) a.s.l. extending NE. One hour and 48 minutes after the eruption, the higher cloud extended ~100 km SE, and the lower portion of the cloud extended ~80 km NE. Due to the heightened volcanic activity, the exclusion zone was increased from a 6.5-km radius to a 7.5-km radius and restrictions to access remained within a radius of 11.5 km from the volcano's summit. No evacuations were ordered. According to a news article, ashfall caused the closure of an airport in the city of Colima, ~30 km away.
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 high point of the complex) on the north and the historically active Volcán de Colima at the south. A group of late-Pleistocene cinder cones is located on the floor of the Colima graben west and east of the 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, producing thick debris-avalanche deposits on three sides of the complex. Frequent historical eruptions date back to the 16th century. Occasional major explosive eruptions have destroyed the summit (most recently in 1913) and left a deep, steep-sided crater that was slowly refilled and then overtopped by lava dome growth.