The risk of an earthquake in Washington

earthquakeSpeaking tectonic terms, a lot of things going on in the north-west Pacific plate. Of the subduction zone (the place of insertion plate in the mantle, in other words, the promotion of the lithospheric plates) Cascadia with lithospheric plate, Juan de Fuca, which is slowly moving under the North American plate. According to legend ideytsev, more than 1100 years ago, there was a powerful earthquake, hence the share of seismic hazard is present here.

Now add to this potentially dangerous changes in Bellingham basin and tectonic activity of the area along the coast of Washington, near the Canadian border. The research team found active tectonic faults in up to 60 km to the north of any previously known faults.

According to one of the participants in the study group, the U.S. Geological Survey geologist, Richard Blakely, has long period, throughout the Pacific Northwest region slowly shrinks from north to south at a rate of a few millimeters per year. This does not seem a lot, as long as you do not represent what the consequences may result.

The fact that he found Blakely and his colleagues, this is reverse faults. Thrust — the type of tectonic fault, where one side of the plate as it is pushed up another. According to geologists, reverse faults are capable of causing an earthquake of magnitude 6 to 6.5 points.
Blakely also studied the map of magnetic anomalies in the area and noticed a few changes that were not there before. Enlisted the help of colleagues from Washington, he was shown a picture Lidar — are collected airborne laser scanning crust. So with the help of it, they found the steep banks, caused by breaks plates, in the same places that already have a record of the fact that an earthquake pushed the ground almost a meter upwards.

Were also found three faults near Birch Bay, Sandy Point and Drayton Harbor, throughout Tihookenskogo coast of North Washington, about 32 miles north of Bellingham.
Moreover, the group found damage from the land towards the sea, which means that underwater earthquakes. And this is a direct result of a tsunami.

The result is to ensure that the speed is not forcing start to worry, but to think is worth. Given the 1000 year-old earthquake and shear rate for sufficient voltage plates to a certain time, exactly how many, no one can say.

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