cascades

For breathtaking volcanic scenery, few places have the variety found in Lassen Volcanic National Park in the Cascade Range of Northern California. The park boasts five varieties of volcanoes: plug domes, cinder cones, lava cones, shield volcanoes and a stratovolcano called Brokeoff volcano (or Tehama volcano). Bubbling hot springs, boiling mud pots and fumaroles in six geothermal fields in the southern part of the park complete the picture.

At any given time, a massive earthquake could strike the coast of the northwestern United States and southwestern Canada, the site of the Cascadia Subduction Zone. Scientists have long known about the potential earthquake threat to major population centers like Portland, Ore., Seattle, Wash., and Vancouver, British Columbia. But scientists thought that the likely place for such a quake was off the coast.

SAN FRANCISCO — After more than three and a half years of continuous eruption, Mount St. Helens in Washington quieted earlier this year. Following intense monitoring efforts, the volcano is officially “asleep,” researchers reported Thursday at the annual meeting of the American Geophysical Union.