Interplate earthquake

An interplate earthquake is an earthquake that occurs at the boundary between two tectonic plates. Earthquakes of this type account for more than 90 percent of the total seismic energy released around the world. If one plate is trying to move past the other, they will be locked until sufficient stress builds up to cause the plates to slip relative to each other. The slipping process creates an earthquake with relative displacement on either side of the fault, resulting in seismic waves which travel through the Earth and along the Earth's surface. Relative plate motion can be lateral as along a transform fault boundary, vertical if along a convergent boundary (i.e. subduction or thrust/reverse faulting) or a divergent boundary (i.e. rift zone or normal faulting), and oblique, with horizontal and lateral components at the boundary. Interplate earthquakes associated at a subduction boundary are called megathrust earthquakes, which include most of the Earth's largest earthquakes. Intraplate earthquakes are often confused with interplate earthquakes, but are fundamentally different in origin, occurring within a single plate rather than between two tectonic plates on a plate boundary. The specifics of the mechanics by which they occur, as well as the intensity of the stress drop which occurs after the earthquake also differentiate the two types of events. Intraplate earthquakes have, on average, a higher stress drop than that of an interplate earthquake and generally higher intensity. Mechanically, interplate earthquakes differ from other seismic events in that they are caused by motion at the boundary between two tectonic plates. An interplate earthquake event occurs when the accumulated stress at a tectonic plate boundary are released via brittle failure and displacement along the fault. There are three types of plate boundaries to consider in the context of interplate earthquake events: Transform fault: Where two boundaries slide laterally relative to each other. Divergent boundary: Where two boundaries move apart.