This week’s featured volcano is a beautiful giant, a classic symmetrical, snow-capped stratovolcano towering over its surroundings and sending small eruptions into the atmosphere. However, it’s the proximity to 21 million people that makes this volcano one to watch. Although the last 1200 years have been fairly quiet, there is a longer history of larger and much more dangerous eruptions.
(Aztec: “Smoking Mountain”)
Popocatépetl at a Glance:
|Located:||México, 70 km SE of Mexico City|
|Volcano Type:||Stratovolcano (both ash and lava eruptions)|
|Summit Elevation:||5426 m (17, 802 feet) – 2nd highest volcano in North America|
|Last Known Eruption:||2011 (continuing since 2005)|
Most Recent Activity (Week of August 29-September 4, 2011): Frequent emissions of gas, ash and steam reported by CENAPRED, along with harmonic tremor (volcanic earthquakes) and possible lahars (ashy mudflows). On August 30, a plume of ash rose 1 km into the air and deposited ash on towns 19 km away.
Historic Deadly Eruptions:
1996 (active ~1994-2003) Moderate eruption. Episodic explosions produce ash and pumice emissions. A small lava dome grows on the crater floor. 5 people were killed close to the crater rim during an explosion in May, 1996.
1919-1920 Moderate eruption. Episodic explosions produce ash and pumice emissions. A small lava dome grows on the crater floor. Several people died inside the crater.
Geologic History: This glacier-clad stratovolcano contains a steep-walled, 400 x 600 m wide crater. 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 Popocatépetl accompanied by pyroclastic flows and voluminous lahars that swept basins below the volcano. For the last 1200 years, eruptions have been minor to moderate in scale (lava domes, ash-producing explosions, fumaroles). In the 20th century, there was a quiet period between 1947 and 1994, when activity resumed. Since 1996 small lava domes have been constructed within the summit crater and destroyed by explosive eruptions. Intermittent small-to-moderate gas-and-ash eruptions have continued, occasionally producing ashfall in neighboring towns and villages.
Info from CENAPRED and the Smithsonian Global Volcanism Network.
This volcano is featured in Volcanic Disaster.