CENAPRED reported that during 3-10 March the seismic network at Popocatépetl recorded between 39 and 211 gas, steam, and ash emissions. Crater incandescence at night sometimes increased coincident with emissions. During 3-4 March there were 45 explosions detected; an explosion at 2004 on 3 March ejected tephra 700 m from the crater onto the NE flank, and other explosions ejected material 100 m onto the flanks. Gas-and-ash plumes drifted NE. On 5 March there were 29 explosions. Ash plumes mostly rose less than 1 km, although one gas, steam, and ash plume rose 3 km and drifted NE. The next day an explosion generated an ash plume that rose 1.2 km and drifted NE. A series of explosions on 7 March produced ash plumes that rose 1-2 km and drifted SW and N. Incandescent tephra was ejected 800 m onto the flanks and ashfall was reported in Ecatzingo (15 km SW). A series of explosions on 8 March produced ash plumes that rose 2 km and drifted NE. Ashfall was reported in Amecameca (20 km NW), Ecatzingo (15 km SW), and Tepextlipa. On 9 March a low-intensity explosion detected at 1014 generated a water vapor, gas, and ash plume. On 10 March two explosions were detected (at 0747 and 0859). The Alert Level remained at Yellow, Phase Two.

Geological Summary. 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.

Source: Centro Nacional de Prevencion de Desastres (CENAPRED)