Report on Colima (Mexico) — 29 June-5 July 2005
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 29 June-5 July 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, 29 June-5 July 2005. Smithsonian Institution and US Geological Survey.
19.514°N, 103.62°W; summit elev. 3850 m
All times are local (unless otherwise noted)
Ash emission continued at Colima during 29 June to 5 July. On 30 June, lahars traveled SW down La Lumbre Ravine and SSE down Montegrande Ravine to a maximum length of ~10 km. The lahars did not reach populated areas. Due to heavy rain, and ash on the flanks of the volcano, Universidad de Colima advised avoiding the ravines of La Lumbre, San Antonio, Monte Grande (in Colima state), and La Arena (in Jalisco state). The Washington VAAC reported that the Colima video camera and satellite imagery confirmed that an explosive eruption occurred at Colima on 5 July at 1821. The Mexico City MWO reported that the resultant ash plume reached a height of ~9.1 km (~29,900 ft) a.s.l. and drifted NW. According to the Colima Volcano Observatory, pyroclastic flows accompanying the eruption traveled down Colima's E flank.
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.