Report on Popocatepetl (Mexico) — 8 April-14 April 2015
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 8 April-14 April 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, 8 April-14 April 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 after a series of explosions ended at 1200 on 7 April the seismic network at Popocatépetl recorded 78 low-intensity emissions through 1100 on 8 April; gas-and-steam plumes containing small amounts of ash drifted SE. Also during this period 93 explosions occurred, and 12 minutes of harmonic tremor were detected on 8 April. During 8-14 April the seismic network recorded 20-112 gas, steam, and ash emissions, and nighttime crater incandescence was often noted. On 9 and 10 April the network detected 41 and 120 minutes of harmonic tremor, respectively. During an overflight on 10 April scientists confirmed that a lava dome was emplaced in the bottom of the crater between 24 March and 4 April. The lava dome was at least 250 m in diameter and 30 m thick. The surface of the dome had concentric fractures and the central part was collapsed from deflation. Explosions were detected during 13-14 April. 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.