Report on Colima (Mexico) — 21 January-27 January 2015
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 21 January-27 January 2015
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2015. Report on Colima (Mexico). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 21 January-27 January 2015. Smithsonian Institution and US Geological Survey.
19.514°N, 103.62°W; summit elev. 3850 m
All times are local (unless otherwise noted)
Based on news articles, an explosion at 0713 on 21 January generated an ash plume that rose 4 km and drifted E. Ashfall was reported in Huescalpa (25 km NE), Tuxpan (25 km ENE), Zapotiltic (23 km NE), Vista Hermosa, Atenquique (20 km E), and Mazamitla (78 km NE). On 23 January authorities restricted access to the Parque Nacional Nevado de Colima citing increased activity during the previous days. The next day an ash plume rose 500 m and was followed by another ash plume that rose 700 m. Two ash plumes on 26 January rose as high as 1 km.
In a 24 January bulletin, the Unidad Estatal de Protección Civil reported that Colima remained active, although there was a slight decrease in the number and size of lava-block avalanches. Lava flows were active on the W and WNW flanks, and explosive activity was low to moderate. The recent explosions had partially destroyed the lava dome. Residents were warned not go within 5 km of 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.