Today's magnitude 8.8 earthquake near Kamchatka is the largest earthquake to have occurred worldwide since the magnitude ~9.1 Tohoku earthquake in 2011.

Today's earthquake occurred in the subduction zone beneath the Kamchatka Peninsula, where the Pacific plate is moving WNW approximately 75 mm/yr and being forced beneath the the Okhotsk plate that forms eastern Siberia and the Kamchatka Peninsula and in some studies is considered part of the North American plate.

Given the earthquake's size and location, and preliminary seismological observations, it is likely to have involved slip of 10+ m over an area of ~150 x 400 km,  although further analysis over the next 12-24 hours will be required to confirm this. Today's earthquake was preceded on 20 July by a magnitude 7.4 earthquake, now recognised as a foreshock.

The depth, size, and faulting characteristics of today's earthquake combined to generate a tsunami that has already affected nearby coastlines and Japan and will have ongoing effects across the Pacific in coming hours. Today's earthquake released approximately 30x more energy than the 2016 magnitude 7.8 Kaikōura earthquake and approximately 3x less energy than the magnitude 9.1 Tohoku earthquake.