Scientists mapped a locked zone behind Kamchatka’s 2025 magnitude-8.8 quake

Image: Serget Ponomarev/NYT When a magnitude 8.8 earthquake ruptured a fault offshore from Russia's Kamchatka Peninsula in 2025, it sent tsunami waves across the Pacific Ocean. Now researchers have shown that clues to where it would strike may have been sitting in ground-motion measurements collected years earlier. By reanalysing older satellite positioning records, a new study maps a major locked zone on the plate boundary that lines up with the rupture, along with smaller patches near the point where it began. The findings help explain why a comparable earthquake in 1952 unleashed a far more destructive tsunami. Here is what the study found.Where the Pacific Plate slides beneath Kamchatka, the subduction zone behind two great earthquakesKamchatka, a peninsula in the northwest Pacific, marks the place where one tectonic plate dives beneath another. According to the study ‘Linking Interseismic Locking to Coseismic Rupture: The 2025 Mw 8.8 Kamchatka Earthquake’ published in Geophysical Research Letters by Axel Periollat and Gareth Funning, the Pacific Plate descends beneath a smaller piece of crust called the Okhotsk Microplate at roughly 80 millimetres a year, a little over three i...