By Rod Hill on 2012-02-15
The 6.0 magnitude earthquake Tuesday, 152 miles west of Bandon, Oregon was the latest quake in the most active quake zone close to the west coast. In fact, the Blanco Transform Fault Zone has triggered some 1,500 earthquakes over the past 40 years. Back in 2008, the zone produced a swarm of 600 quakes over a ten day period. Doctor John Nabelek, with Oregon State University is a lead researcher of the Blanco Fault Zone and says despite the active zone,a tsunami is highly unlikely. The movement of a transform fault is horizontal in nature, as the plates move sideways past each other. This type of motion does not create enough vertical displacement on the ocean floor to generate tsunamis. The professor's research indicated the strongest possible quake in the area could be a 6.5 magnitude. He believes a 6.0 quake like Tuesday's is generated once each five years.
The active fault zone is close enough to the west coast to be picked up by many of the 60 land-based seismographs deployed from British Columbia to California. This fact, makes the zone a unique scientific learning experience for geologists. Dr. Nabelek, says the transform fault is similar to the well known San Andreas. The Blanco Zone is more active, but the San Andreas has the potential to produce stronger magnitude quakes, a fact California knows all too well.
Weak earthquakes near magnitude 1.0 occurred Tuesday near Sherwood, Oregon and Hockinson, Washington.
One well know reason for the high number of earthquakes near the west coast is the northward movement of the Pacific Plate. The fault of the Pacific Plate is off of the Northwest coast, but inland across California. Areas west of the fault are pushing northward at the rate of about 1.5" each year. Scientist estimate the land know as Los Angeles will move to the north, passing present day San Francisco in roughly 20 million years!
Time running out for cold winter weather