Cotopaxi Volcano, Ecuador

Abstract

Cotopaxi (0°42′S, 78°24′ W) is a stratovolcano with a summit elevation of 5,911 m above sea level. It has erupted 50 times since 1738. The 1877 eruption melted snow and ice on the summit, which produced mudflows that traveled a distance of 100 km far from the volcano top. Recent weak volcanic activities, in 1975–1976, consisted of an increase in steam emissions, melting snow, and small earthquakes occurrence. The stratovolcano Cotopaxi is one among the famous active volcanoes located in the mountain range of the Ecuador Eastern Cordillera of the Andes. The present steep cone was formed about 5,000 years BC; later, it was completed by a group of side craters. Massive lava flows often reached the mountain roots and caused severe damages. During the periods of relative inactivity, the summit used to be covered by a glacier; the renewed volcanic activity was usually accompanied by lahars, flows of mud composed of pyroclastic material, and water that rushed down from the summit, dredging deep valleys. A horrible catastrophe occurred in 1877, when huge black masses of volcanic debris, water, and muddy ashes rolled down with unbelievable speed and the lahar front reached upto the 100 km-distant Pacific coast on the west and the rim of the Amazonian Basin on the east. The strongest eruptions of Cotopaxi occurred in 1743, 1768, 1853, and 1877. The most recent prominent disaster dates back to 1904, with several minor events in 1939, 1940, and 1942.