Report on Popocatepetl (Mexico) — March 1995
Bulletin of the Global Volcanism Network, vol. 20, no. 3 (March 1995)
Managing Editor: Richard Wunderman.
Popocatepetl (Mexico) Ash plumes; two SO2-flux measurements from January (1-4 kilotons/day)
Please cite this report as:
Global Volcanism Program, 1995. Report on Popocatepetl (Mexico). In: Wunderman, R. (ed.), Bulletin of the Global Volcanism Network, 20:3. Smithsonian Institution. https://doi.org/10.5479/si.GVP.BGVN199503-341090.
19.023°N, 98.622°W; summit elev. 5393 m
All times are local (unless otherwise noted)
. . . SO2 flux was estimated twice during January using COSPEC. On 15 January scientists made airborne measurements but were unable to establish a GPS navigational fix for 2-3 hours and so made wind speed estimates from map positions and estimates by their pilot, Sergio Zambrano. On 28 January the plume was traversed by a van on a route between the Puebla airport and a junction N of Atlixco; wind speed was from pilot reports to the Puebla airport. Two 15-minute eruptions of dark ash were noted (at 0922 and 1015). Results of these SO2 flux measurements were as follows: 1) 15 January, 3,680 ± 300 tons/day; 2) 28 January, 2,000 ± 1,000 tons/day.
At 1000 on 27 January a light beige plume rose no more than 100-200 m above the crater rim and was visible downwind for about 100 km. In addition, sufficient ash fell on the Puebla airport during the night of 27 January to make the tarmac (airport surface) light in color and to visibly cover freshly washed planes.
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.
Information Contacts: Stan Williams, Tobias Fisher, and Caitlin Gorman, Arizona State University, USA; Claus Siebe and Hugo Delgado, Instituto de Geofísica, UNAM, Coyoacan.