Report on Popocatepetl (Mexico) — 7 December-13 December 2005
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 7 December-13 December 2005
Managing Editor: Gari Mayberry
Please cite this report as:
Global Volcanism Program, 2005. Report on Popocatepetl (Mexico). In: Mayberry, G (ed.), Weekly Volcanic Activity Report, 7 December-13 December 2005. Smithsonian Institution and US Geological Survey.
19.023°N, 98.622°W; summit elev. 5393 m
All times are local (unless otherwise noted)
On 1 December at 0653, a moderate explosion at Popocatépetl produced an ash plume to a height of ~5 km above the volcano's summit (or 34,200 ft a.s.l.). An intense episode lasted ~2 minutes, and was followed by high-frequency tremor for 30 minutes. Ash drifted NE and fell in Amecameca, ~20 km NW of the volcano. An explosion on 1 December at 0920 produced an ash plume to ~2.5 km above the summit (or 26,000 ft a.s.l.) that also drifted NE. After this explosion, there was an increase in the number of small explosions, some of which involved small amounts of ash. After an explosion on 4 December, ash fell in the states of Tlaxcala (50 km NE of the volcano) and Puebla (60 km E of the volcano) and the volcanic activity returned to previous lower levels. As of 12 December, only emissions of steam and gas occurred.
Geologic Background. Volcán Popocatépetl, whose name is the Aztec word for smoking mountain, rises 70 km SE of Mexico City to form North America's 2nd-highest volcano. The glacier-clad stratovolcano contains a steep-walled, 400 x 600 m wide crater. The generally symmetrical volcano is modified by the sharp-peaked Ventorrillo on the NW, a remnant of an earlier volcano. At least three previous major cones were destroyed by gravitational failure during the Pleistocene, producing massive debris-avalanche deposits covering broad areas to the south. The modern volcano was constructed south of the late-Pleistocene to Holocene El Fraile cone. Three major Plinian eruptions, the most recent of which took place about 800 CE, have occurred since the mid-Holocene, accompanied by pyroclastic flows and voluminous lahars that swept basins below the volcano. Frequent historical eruptions, first recorded in Aztec codices, have occurred since Pre-Columbian time.