Mount Shasta, a steep-sided Cascade Range stratovolcano in Northern California, looms above Little Glass Mountain, a thick obsidian flow erupted from the Medicine Lake shield volcano about 1,000 years ...

Mount Rainier, America's most dangerous volcano, could devastate 60,000 people in 30 minutes via lahars - no eruption ...

Hoping to make the system clearer to the public and emergency officials, the U.S. Geological Society has revamped its nationwide volcano warning level system. Starting Sunday there will be four ...

For three days, a remote volcano off the Pacific Northwest coast has been shaking almost nonstop, a deep rumble beneath the ocean that has ricocheted across social media as a supposed warning shot for ...