Sabancaya
Sabancaya is an active stratovolcano in the Andes of southern Peru, about northwest of Arequipa. It is the most active volcano in Peru and is part of a north-south chain of three major stratovolcanoes, including the extinct and eroded Nevado Hualca Hualca at the northern end, the dormant Nevado Ampato to the south, and Sabancaya in the middle. Sabancaya hosts several glaciers which cover an area of about and descend as low as on its flanks.
Volcanic activity
The andesite stratovolcano of Sabancaya has been very active during historic times, with the earliest recorded eruptions in 1695 and 1758 . Following over 200 years of dormancy, satellites detected an increase in thermal emission in July 1986 and intense activity resumed in December of that year, with several eruptive cycles over the next two years producing a lava dome in the crater.
The most sustained period of activity began with explosive eruptions on May 28, 1990, and continued for over eight years. The eruptive cycle rated a VEI of 3, with more than of lava flows and tephra produced over that period. At the height of the activity in 1994, eruptions producing large ash clouds occurred every two hours. Although published topographic maps have not been revised since the eruptive cycyle, it is suspected that the cone may have grown to just over during that time. Additional smaller eruptions occurred in 2000 and 2003.
Volcanic hazards
Sabancaya is considered one of the most hazardous volcanoes in Peru, along with the massive Coropuna and the cone of El Misti near Arequipa. As of the mid-1990s, over 8,000 people lived in the valleys draining the flanks of the volcano. Potential hazards include lahars and pyroclastic flows down the Majes, Colca, and Siguasi river drainages. During the 1988 eruption, cattle died in nearby areas either directly from poisonous volcanic gases or from eating contaminated vegetation.
References
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article Sabancaya
