What are the different types of earthquakes, and which are stronger?
There are three types of earthquakes: shallow, deep, and subduction. Shallow Earthquakes (“Crustal” quakes) are caused by faults in the continental plates, as a result from the relative motion of sections of the plates. They are usually 1 to 5 magnitude, less than 15 miles deep, occur random and unpredictable and most of them are not even felt. Deep Earthquakes (“Intra Plate” quakes) occur between the subducting oceanic plates as they bend beneath the continental plates. They are 6.0 to 8.0 magnitude, occur up to 40 miles deep and occur every 20 to 30 years along a given fault line. Subduction Earthquakes are huge quakes that result when the boundary between the oceanic and continental plates ruptures. This contact is not smooth and a great deal of energy accumulates from the motion of the plates. In 1700, the most recent Cascadia Subduction Zone earthquake sent a tsunami as far as Japan. They have a 8.0+ magnitude and occur every 100-1,000 years along a given fault line.
