An explosion seen off the Caspian Sea on July Fourth was attributed to a mud volcano eruption. Gavriil Grigorov via Getty Images A mud volcano erupted on an island in the Caspian Sea about 46 miles ...

Mud Volcano trail is the perfect place to explore some of Yellowstone National Parks hydrothermal features. This area of thermal features includes the Mud Volcano, Mud Geyers, Dragon's Mouth Spring, ...

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