Report on Popocatepetl (Mexico) — 21 March-27 March 2018
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 21 March-27 March 2018
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2018. Report on Popocatepetl (Mexico). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 21 March-27 March 2018. 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 16 March scientists observed a small lava dome, number 78, at the bottom of the inner crater. The dome was 50 m in diameter and 30 m thick, and produced gas plumes visible above the main crater rim. The inner crater was 320 m in diameter and about 100 m deep; remnants of the previous dome had been deposited on the walls of the inner crater. Each day during 21-27 March there were 20-233 emissions, often containing slight amounts of ash. Incandescence from the crater was visible at night. Plumes of gas and water vapor drifted WSW, SSW, SSE, and SE. 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.