Mud volcano erupting in Azerbaijan
Here a photographer has caught a mud volcano literally in the act; spurting mud upward into the air.
A mud volcano is a place on the Earth where a mixture of water, gases, and mud pours out from beneath. As mud dries, it will solidify, so mud volcanoes often build cones around them that resemble the shapes made by solidifying lava on the slopes of volcanic cones, even if the ones around mud volcanoes are smaller.
For a mud volcano to occur, a couple conditions must be present. There must be mud, mixed with water, and there must be some pressure gradient that drives the mud up to the surface through a crack. These conditions can be met in areas that are hydrothermally active, as occur in Yellowstone, or in areas that are full of gassy hydrocarbons like Azerbaijan.
Azerbaijan hosts several hundred mud volcanoes, more than any other country in the world. The mixture of mud and water is carried to the surface as natural gas leaks out from below; effectively marking the locations of some of the country’s gas fields. Some of these leaks will constantly stay on fire; others will actually explode on occasion.
-JBB