Because Pico de Orizaba has not erupted for centuries
people might think itis not a hazardous volcano. A look at a simple
geologic map (based on Cantagrel, 1984) tells a different story. Several
eruptions in the last 13,000 years have sent pyroclastic flows down the
volcano. These flows were often channeled into river valleys and towards
population centers. These type of eruptions have happened every
1,000-2,000 years in the past. The last large eruption with pyroclastic
flows was 3,400 years ago. Future eruptions will probably also include
highly mobile pyroclastic flows. The black arrows show the paths of older
Saint-Vincent type pyroclastic flows.The white arrow shows the path of
Dark stars mark dacite
domes. Dark areas covered by ash and block Pelean nuee ardentes. Major
streams shown in blue.
Sources of Information
Cantagrel, J.M., Gourgaud, A., Robin, C., 1984, Repetitive mixing events
and Holocene pyroclastic activity at Pico de Orizaba and Popocatepetl
(Mexico): Bull. Volcanol., v. 47, p. 735-748.
Hoskuldsson A, C Robin, 1993, Late Pleistocene to Holocene eruptive
activity of Pico deOrizaba, Eastern Mexico. BV55, 571-587.
Simkin, T., and Siebert, L., 1994, Volcanoes of the World:
Geoscience Press, Tucson, Arizona, 349 p.
Williams, H., and McBirney, A.R., 1979, Volcanoes: San Francisco,
Freeman,Cooper and Company, 397 p.