- VolcanoAzufral volcano (Azufral de Túquerres) is a stratovolcano in southern Colombia with a 2.5x3 km wide caldera 35 km SW of Galeras volcano. The last eruption took place about 1000 years ago.
Volcano type stratovolcano normal or dormant Location Colombia Summit elevation 4070 m / 13,353 ft Azufral volcano eruptions 930 BC (?), 1650 BC ± 150, 1850 BC (?), 2095 BC ± 100 Typical eruption style explosiveAzufral's caldera contains a complex of several Holocene rhyodacitic lava-domes.
The crescent-shaped Laguna Verde lake occupies the NW side of the caldera. Laguna Verde is an acid lake (pH 2.4)) with hot springs on the NE shore of the lake (temperatures of 54°C, pH of 2.6, measured in 1990).
The latest lava dome in the caldera was formed about 3600 years ago and still has active fumaroles.
Azufral volcano's lavas contain more silica than the nearby volcanoes and rhyolitic-dacitic tephra deposits from explosive activity mantle the volcano.