Hi All. “New analysis by Oregon State University marine geologist Chris Goldfinger and his colleagues have provided fresh insights into the Northwest's turbulent seismic history -- where magnitude 8.2 (or higher) earthquakes have occurred 41 times during the past 10,000 years.” This has caused some to rethink what they know.
Understanding the Cascadia Subduction Zone history is complicated by the possibility that major earthquakes in the northern segment have occurred in "clusters." A thousand years may go by without a major event, and then an earthquake would occur every 250 years or so.
"We're just starting to understand the whole idea of clusters and there isn't consensus on whether we are in one or not," Goldfinger said, "but that possibility does exist, which further suggests that we may experience a major earthquake sooner than later." This means there could be a major quake tomorrow, or we still have 700 more years to prepare for it. No one really knows.
“The last major earthquake to hit the Cascadia Subduction Zone was in January of 1700. Their knowledge about what happened in Oregon and Washington is more speculative, but the consensus -- gleaned from studies of coastal estuaries, land formations, and river channels -- is that the physical alteration to the coast was stunning.”
Another area seismologists are looking at is the Blanco Transform Fault Zone. “The Blanco Transform Fault Zone likely won't produce the huge earthquake many have predicted for the Pacific Northwest because it isn't a subduction zone fault. But the scientists say an earthquake of magnitude 6.5 to 7.0 is possible, if not probable in the near future, and their analysis suggests that the region may be under some tectonic stress that potentially could affect the Cascadia Subduction Zone.” It has more quakes then the San Andreas fault in California. Now that is something to think about. Take Care...Don
http://www.sciencedaily.com/releases/2008/08/080826124413.htm
http://www.sciencedaily.com/releases/2010/05/100524121250.htm
Understanding the Cascadia Subduction Zone history is complicated by the possibility that major earthquakes in the northern segment have occurred in "clusters." A thousand years may go by without a major event, and then an earthquake would occur every 250 years or so.
"We're just starting to understand the whole idea of clusters and there isn't consensus on whether we are in one or not," Goldfinger said, "but that possibility does exist, which further suggests that we may experience a major earthquake sooner than later." This means there could be a major quake tomorrow, or we still have 700 more years to prepare for it. No one really knows.
“The last major earthquake to hit the Cascadia Subduction Zone was in January of 1700. Their knowledge about what happened in Oregon and Washington is more speculative, but the consensus -- gleaned from studies of coastal estuaries, land formations, and river channels -- is that the physical alteration to the coast was stunning.”
Another area seismologists are looking at is the Blanco Transform Fault Zone. “The Blanco Transform Fault Zone likely won't produce the huge earthquake many have predicted for the Pacific Northwest because it isn't a subduction zone fault. But the scientists say an earthquake of magnitude 6.5 to 7.0 is possible, if not probable in the near future, and their analysis suggests that the region may be under some tectonic stress that potentially could affect the Cascadia Subduction Zone.” It has more quakes then the San Andreas fault in California. Now that is something to think about. Take Care...Don
http://www.sciencedaily.com/releases/2008/08/080826124413.htm
http://www.sciencedaily.com/releases/2010/05/100524121250.htm