A great earthquake have been predicted in the Pacific northwest coast around the Cascadia Fault that stretches more than 700 mile on the Northwest Pacific ranged from California city heading to the Vancouver Island, Canada. The Cascadia is a subduction fault zone which is located north of San Andreas Fault. The predicted earthquake that would occur is called the big one. However, it has been better known that in places like San Andreas Fault during this time will be more likely to be a large earthquake. Not known that the earthquake generated in Cascadia fault could occur with a greater energy than that produced in San Andreas Fault. The strength of the earthquake located on Cascadia could be 30 times greater. The power could reach a maximum of 9.2 magnitude compared to 8.5 magnitude resulting on rupture of San Andreas Fault. If this is happened, the massive earthquake in Sacramento, Seattle and Portland will threaten approximately 7 million people in area.
According to seismologists, in Cascadia Fault, the earthquake has been overdue at around 60 years because the earthquake in the Northwest Pacific should have happened 72 years earlier or occur every 240 years, latter in 1700. This discovery is known as the study took this example in a sea ground surface which results showed that there are known 40 subduction zones to be existed for 10.000 years.
Scientists are experiencing the same problem in predicting the time when earthquake will be triggered. The best thing is to prepare for the event. In the history of the San Francisco earthquake in 1906 and the Loma Prieta earthquake in 1989 in California, Sacramento just felt the vibration and there were no great danger. It could be said that the earthquake in Sacramento was rare. Earthquake in 1906 has claimed 3,000 victims. The power of magnitude depended on how large the margin of rupture as a result of the slip of the fault zone. If the size of the rupture is full, it will result in a great earthquake and trigger a Tsunami from the Pacific Northwest coast. Tsunami will reach the Northwest Pacific coast line after 15 minutes of the earthquake which occurred about 4 minutes.
Cascadia Subduction Zone
Estimates there will be about at least 10.000 deaths and 20.000 wounded. In Cascadia fault or subduction zone, there are two plates, namely the North American tectonic plate that is subducted over the Juan de Fuca oceanic plate. The oceanic plate slides under the North American plate distressed over the Juan de Fuca and pressed eastward as much as 3 – 4 centimeters per year. If Cascadia margin slip portion is half, there will be an earthquake about 8 to 8.5 magnitude but if there will be a full margin slip there will be 8.5 – 9.2 magnitude earthquake.
Plus, there will be approximately six feet slide of the land and the maximum of one hundred feet movement of the land to the west after the tension were discharge in an overdue earthquake. The scientist had hoped that there will be a mistake in the science. When the Napa earthquake happened in 2014, the area of earthquake in Sacramento was trembled by a quake but there was no big threat. However, if the big one is happened, it will be hammered as well.