Report on Popocatepetl (Mexico) — 18 February-24 February 2015
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 18 February-24 February 2015
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2015. Report on Popocatepetl (Mexico). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 18 February-24 February 2015. Smithsonian Institution and US Geological Survey.
19.023°N, 98.622°W; summit elev. 5393 m
All times are local (unless otherwise noted)
CENAPRED reported that during an overflight of Popocatépetl on 17 February volcanologists observed dome number 55, 150 in diameter, at the bottom of the inner crater (formed in July 2013) which was 100 m below the floor of the main crater. Each day during 18-24 February the seismic network recorded between 47 and 166 low-intensity events, accompanied by steam-and-gas emissions that visibly contained minor amounts of ash most days. Incandescence from the crater was noted some nights. On 18 February five explosions generated plumes that rose no more than 1 km and drifted NE. A series of small explosions detected during 0844-1300 was accompanied by periods of harmonic tremor. On 21 February there were 22 small explosions, some of which ejected tephra 200 m onto the NE flank. Another series of small explosions, detected from 2221 on 22 February to 0220 on 23 February, were again accompanied by periods of harmonic tremor. Steam, gas, and ash plumes drifted SW on 24 February. The Alert Level remained at Yellow, Phase Two.
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.