An Overview of the Iranian Quaternary Volcanic Centers and Their Hazards

The latest stage of magmatic activities in the Turkish-Iranian plateau is the release of volcanic lavas from the important volcanic centers. The Quaternary volcanic centers (Damavand, Sahand, Sablan, Taftan, and Bazman) are scattered in the Iranian plateau. Most of the Quaternary lavas have reached the Earth's surface due to the activities of major faults. The main composition of these lavas is a range from basalt, basaltic andesite, andesite, trachyte andesite, to trachyte. Petrographic, mineral chemistry and volcanological studies have already been done to characterize the magmatic system of these rocks.

These five volcanic centers are located near the capital city, large and small cities, and villages; therefore, volcanic activities directly threaten many people and can represent just as much of a threat to human life and economies.

Most Iranian volcanic hazards occur many years after volcanic activities. They involve lavas and pyroclastic flows buried by the ash of eruptions, the heat caused by burning clouds, the movement of lahars, the emission of toxic volcanic gases, and underground water and spring pollution. Although all of Iran’s Quaternary volcanoes are dormant, there are still risks from fumaroles, landslides, and contamination of local aquifers. Damavand volcano is a large dormant stratovolcano in the Alborz Mountain Belt, in the Iranian high plateau. This young composite cone is in northern Iran, ~50 km north of Tehran, and is the highest mountain (elevation ~5671 m) in the Middle East and South Asia. Thermal anomalies related to geothermal activities have been revealed based on remote sensing models that theoretically confirm the existence of hot zones containing melt at shallow depths. The thermobarometric studies show that magma under the Damavand volcano is in a network of magma pockets at depths between 2 and 11 km (0.6 and 3 kbar). The fumarolic gases near the summit are related to the magmatic activities in a low-depth magma chamber. There are limited historical activities in Damavand volcano, indicating low risks (landslide, water pollution, fumaroles), and very uncertain risks.