IntroductionGaleras volcano is a stratovolcano located just a few kilometers west of the city of Pasto, Columbia. The volcano reaches an elevation of 14,029 ft. Historically it is one of the most active volcanoes in the country, and is characterized by a large, breached caldera. Inside the breached caldera is a central cone that is slightly lower than the caldera rim, which has been the location of numerous explosive eruptions since the time of the Spanish Conquistadors. Widespread fallout and pyroclastic flow have been deposited by these recent eruptions (Smithsonian institution global volcanism program, n.d.).
Tectonic Setting The Galeras volcanic complex is located in the Colombian segment of the South American Andes, near the border of Ecuador. This mountain range, and Galeras volcano, are a direct result of the collision between the Panamanian tectonic block and South America. The Panamanian tectonic block was detached from the South American continent and pushed upward and northward. This thrusting in combination with the subduction of the Nazca plate under the Colombian block created the Northern Andes mountain range, and in turn, Galeras Volcano (Ball, n.d.). |
Figure 2: Cross sectional view of Galeras volcano tectonic setting. Retrieved from http://geology.com/volcanoes/galeras/
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Figure 3: Location of Galeras volcano (A) as viewed from Google Earth. Retrieved from Google Earth software.