Los Azufres volcanLos Azufres volcano is a large Pleistocene caldera and volcanic complex in central Mexico located about 200 km NW of Mexico City.
It is one of several volcanic complexes north of the axis of the Trans-Mexican Volcanic Belt and still has a very active geothermal system with fumaroles and sulfur deposits (hence its name, the "sulfurous ones") and hot springs.
Introduction:The Los Azufres center consists of a 18 x 20 km wide early Pleistocene caldera that was later partially filled by dacitic-to-rhyolitic lava domes. Eruptions at the Los Azufres volcano can be placed into 2 magmatic cycles, each lasting about 200,000 years, between 1.4 and 0.8 million years ago and 0.6-0.2 million years ago.
During each cycle, eruptions of silicic magma were followed by basaltic volcanism. The latest magmatic cycle produced uplift and lava domes at the southern part of the caldera.
The latest paroxysmal eruptions in the Los Azufres caldera produced ignimbrites between 38,000 and 26,000 years ago. The still active geothermal areas are located along E-W-trending faults.
Los Azufres geothermal field
The 35 sq km Los Azufres Geothermal Field was discovered in 1972 and has been exploited for geothermal energy since 1982, producing 88 MW.
Future eruptions of Los Azufres caldera?
Similar to many calderas of this size (often called "supervolcanoes"), it is possible that there is still an active magma chamber containing large volumes of highly differentiated magma is located at shallow depth, and future eruptions are possible.
- Smithsonian / GVP volcano information
- Ferrari et al (1991) "Geology of Los Azufres caldera, Mexico, and its relationships with regional tectonics", J. of Volcanology and Geothermal Res., v. 47, pp. 129-148
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