Mexico
19.85 N, 100.63 W
summit elevation 3400 mn
Caldera
Los Azufres Volcano is located in central Mexico 200 km NW of Mexico City. The volcano contains Hot springs and fumaroles.
Los Azufres Geothermal Area
Los Azufres is a heavily fractured and faulted volcanic hydrothermal system in the
northern portion of the Transmexican volcanic belt, 80 km east of Morelia city. The area covers 40 sq km.
The geothermal area has been under commercial exploitation to generate electricity since 1982. In 21 years of continuous development, 120 million of tons of steam
have been extracted.
Radon release before 1985 Earthquake
In 1985, about 2 months before the magnitude 8.1 Mexico earthquake, an increase in radon concentration was observed at the volcano. Radon concentrations observed at the geothermal area returned to 'normal' soon after the earthquakes.
Eruptions at Los Azufres Volcano
Los Azufres has a long history of eruptions covering more than 1.5 million years. during this time there have been two main periods of volcanic activity..
1) From 1.5 million - 0.8 million years ago. Two periods of eruptions lasting 200,000 years each. These eruptions were the result of successive eruptions from a shallow magma reservoir.
2) About 0.6 Million years ago, resurgent doming from deep magma supplies led to uplift of the southern part of the caldera.
It is hypothesised that a voluminous differentiated magma body is located at shallow depth, and therefore volcanic activity has not yet finished.
26.000-38.000 years ago.