Coast of British Columbia and south eastern Alaska are frequently hit by strong earthquakes originating from a complex system of faults that give high magnitude shakes. The close examination of the two most recent major events - the Mw 7.8 Haida Gwaii and Mw 7.5 Craig events - revealed valuable information with regards to the interaction between the Pacific and North America plates and the fault complexity of the region. All research findings are included in 19 technical articles of a special issue published by the Seismological Society of America.
The increase in the frequency of low intensity tremors, originating from the San Andreas Fault, about 10 hours after the magnitude 6 Napa earthquake last August, and an observed increase in two other locations, frequently struck by earthquakes, has set the ground for a comprehensive search for tremors across the state. Watch the video with UC Berkeley seismologist Peggy Hellweg describing how "Tremorscope" a new technology may explain a possible connection between tremors and earthquakes.
During the Neoproterozoic, a geological era which occurred about 542 million to one billion years ago, Earth experienced unusual episodes of global cooling that geologists refer to as ''Snowball Earth''.