The U.S. Geological Survey is updating its volcano threat assessments for the first time since 2005.

Volcanologists at the U.S. Geological Survey’s California Volcano Observatory have spent decades mapping Mount Shasta’s geologic history. When it came to rocks dated to 1786, no evidence of ...

Northern California's Mount Shasta was included in the top five Thursday on a list of 18 U.S. volcanoes classified as having "very high threat" by the U.S. Geological Survey.