Popocatepetl, Mexico


Location: 19.0 N, 98.6 W
Elevation: 17,925 feet (5,465 m)
Last Updated: March 11, 2005

A plume of steam and ash rises above Popocatepetl, whose Aztec name means "Smoking Mountain." This December 1994 aerial view is of the NE side of the massive stratovolcano, which towers more than 3200 m above the Valley of Mexico to the right. Frequent historical eruptions have been recorded since the precolumbian era. El Ventorrillo, the small peak on the right skyline, is the summit of the eroded Nexpayantla volcano, a predecessor to the modern cone of Popocatepetl. Photo courtesy of CENAPRED, Mexico City, 1994.

Volcán Popocatepetl, whose name is the Aztec word for smoking mountain, towers to 5426 m 70 km SE of Mexico City to form North America's 2nd-highest volcano. The glacier-clad stratovolcano contains a steep-walled, 250-450 m deep 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 south of the volcano. The modern volcano was constructed to the south of the late-Pleistocene to Holocene El Fraile cone. Three major plinian eruptions, the most recent of which took place about 800 AD, have occurred from Popocatepetl 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 precolumbian time.

Left: Photo taken by the American Landsat satellite on 27 Dec. 1980. The area shown is about 30 km wide (~20 miles), and the smallest object visible is about 30 m across. A long mountain range is in the center of the picture. The dark parks are covered by forests. Popocatepetl is the volcano near the bottom of the range, and the white, snow-covered ridge near the middle is Iztaccihuatl, another volcano which has not erupted during the last few thousand years. Near the top is Tlaloc, a much older volcano that is extinct.

Right: Enlargement of the Popocateptl part of the first one. If you look closely you can see the crater at the top of Popocateptl. The eruptions are coming from within the crater. Do you wonder what the black pluses are on these images? They are not giant marks on the ground, but are tiny, equally spaced marks on the satellite camera. If there are any distortions in a satellite image, scientists can check the distances between the pluses to make correction. Most satellite cameras don't have these pluses - or fiducial marks, as they are called.

Volcanic Explositivity Index: 1-2

Popocatepetl, the second highest volcano in Mexico, is a giant stratovolcano, 70 km (~45 miles) southeast of downtown Mexico City, and 45 km (~30 miles) southwest of the city of Puebla.

Popo - as many people call it rather than struggling with its full name (Popo-cat-e-petal) - became active just before Christmas after five decades of quiet. During the last two years the volcano has frequently had a small column of steam rising from its summit crater. After midnight on December 21, 1994 a series of earthquakes signaled that eruptions had started. That morning a gray ash cloud was visible over the top of the volcano, and ash fell on Puebla.

During the afternoon, the eruptions increased. Because most of the ash was blowing to the east, civil defense authorities decided to evacuate 19 villages (31,000 people) east of Popo. Moderate eruptions have continued, and according to newspapers the total number of evacuees was about 75,000 people by December 26. The United States Geologic Survey has sent a team of volcano experts to Mexico to help Mexican scientists evaluate what the volcano may do in the near future. The volcano has been quite for more than a week now.

Background Information:

Popo is one of the most active volcanoes in Mexico, having had 15 eruptions since the arrival of the Spanish in 1519 AD. The Aztec Indians who lived in Central Mexico recorded additional eruptions in 1347 and 1354. Most of the eruptions in the past 600 years were relatively mild, with ash columns rising only a few kilometers above the summit.

Volcanologists have studied Popo because most volcanoes tend to have future eruptions that are like their earlier ones. Thus, the volcano's past history helps us prepare for possible future activity. One very important reason to try to predict future eruptions is that more than 20 million Mexican people live close enough to the volcano to be threatened by its eruptions.

NASA satellite image and information about Popocatepetl .

Additional NOAA images of Popocatepetl taken on 10 October 1996 .

Additional information about Popocatepetl is available on the homepage of the Cascade Volcano Observatory .

Popocatepetl Volcano News provides additional information about the eruption.

CENAPRED , additional disaster preparation information.

Sources of Information:

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