The July 16, 2023, M 7.2 earthquake occurred as the result of thrust faulting on the subduction zone interface between the Pacific and North American plates. The source modeling indicates rupture occurred on a shallowly dipping fault to northwest. At this location, the Pacific plate converges with North America to the northwest at a rate of about 70 mm/yr, subducting along the Alaska-Aleutians trench 125 km to the southeast of the earthquake.
While commonly plotted as points on maps, earthquakes of this size are more appropriately described as slip over a larger fault area. Finite source modeling indicates ruptured fault size for this earthquake of about 40x25 km (length x width).