Report on Popocatepetl (Mexico) — 16 November-22 November 2011
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 16 November-22 November 2011
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2011. Report on Popocatepetl (Mexico). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 16 November-22 November 2011. Smithsonian Institution and US Geological Survey.
19.023°N, 98.622°W; summit elev. 5393 m
All times are local (unless otherwise noted)
During 16-20 November CENAPRED reported steam-and-gas emissions from Popocatépetl. A series of emissions was detected on 18 November; clouds prevented ground observations and no ashfall was reported. Based on information from the Mexico City MWO however, the Washington VAAC reported that an ash plume rose to an altitude of 7.6 km (25,000 ft) a.s.l. and drifted SW that same day. Satellite imagery showed another ash plume drifting E at an approximate altitude of 9.1 km (30,000 ft) a.s.l. CENAPRED noted that at 1201 on 20 November an explosion produced an ash plume that rose approximately 2 km above the crater and drifted N. The explosion was heard in Amecameca (19 km NW). Steam-and-gas plumes rose from the crater during 21-22 November.
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.