Report on Popocatepetl (Mexico) — 20 July-26 July 2005
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 20 July-26 July 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, 20 July-26 July 2005. Smithsonian Institution and US Geological Survey.
19.023°N, 98.622°W; summit elev. 5393 m
All times are local (unless otherwise noted)
Several low-intensity emissions occurred at Popocatépetl during 21-25 July. On 21 July at 0906, an emission produced a plume to a height of ~2 km above the volcano's crater (~24,400 ft a.s.l.). Based on information from the Mexico City MWO, the Washington VAAC reported that ash visible on the web video camera rose to ~2.8 km above the crater (27,000 ft a.s.l.). The Alert Level at Popocatépetl remained at Yellow Phase I.
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.