During 27 February- 2 March volcanism at Colima was similar to the previous week. Avalanches of incandescent material continued to travel down the volcano's S, SW, and W flanks. They extended 2-3 km from the volcano's summit and were recorded seismically. Block lava continued to flow down the SW flank of the volcano, extending as far as 240 m from the summit. By 28 February the flow was 15 m high, 55 m wide, and had a volume of about 200,000 m3. Lava was also visible flowing as far as 2 km down the volcano's W flank, and down the E flank. The Washington VAAC received reports that an emission of steam-and-ash on 4 March at 1045 produced a volcanic cloud to a height of ~4.3 km a.s.l.

Geological Summary. The Colima 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 scarp, 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 recorded 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.

Sources: Centro Universitario de Estudios e Investigaciones de Vulcanologia - Universidad de Colima, Washington Volcanic Ash Advisory Center (VAAC)