The geology beneath the Noto Peninsula is a slow-motion collision. The earthquake occurred in a zone of compressional deformation where the Okhotsk microplate converges westward into the Amur Plate at roughly 9 millimeters per year, with a maximum convergence rate of 24 millimeters per year. Both are relatively small tectonic plates wedged between the massive Pacific and Eurasian plates, which themselves converge at about 90 millimeters per year. This convergence creates reverse faults -- fractures where one block of rock is pushed up and over another -- and the 2023 earthquake's focal mechanism confirmed exactly that pattern. The shaking was intense enough that seismic intensity maps suggested shindo 7 -- the maximum on Japan's scale -- may have been reached at Noroshi in Suzu, though official readings recorded shindo 6-upper.

Thirty-eight houses collapsed outright. Another 263 were partially destroyed. A further 1,855 sustained damage, with the overwhelming majority -- 1,825 -- concentrated in Suzu. Among the injured, two fell unconscious, two were trapped in collapsed structures, a child was struck by a falling wardrobe, and another suffered burns. Two people were in serious condition. But the image that captured the peninsula's vulnerability was not a fallen house. It was Mitsukejima, the solitary rock island standing 30 meters above the sea off Suzu's coast. The formation, made of soft diatomaceous earth and already shrinking from wind and rain erosion, partially collapsed. It had already been damaged by a shindo 6-lower earthquake the previous year. Each tremor was taking a piece of Battleship Island with it.

Around 1,600 people were evacuated across the affected area, with 250 taking shelter in evacuation centers in Ishikawa Prefecture. The Japan Meteorological Agency warned that strong aftershocks could continue for at least a week, and more than 50 hit on the first day alone, ranging from magnitude 2 to 5, including a magnitude 5.6 aftershock at 9:58 p.m. and a magnitude 4.5 at 11:18 p.m. Over 120 homes lost water supply. Prime Minister Fumio Kishida announced that additional measures would be taken. But the mayor of Suzu, after issuing an earthquake emergency advisory and ordering evacuations, made a notable decision: the city would not request assistance from the Japan Self-Defense Forces. The damage, he judged, could be managed locally. It was a decision rooted in civic pride -- and perhaps in the assumption that the worst was over.

The 2023 earthquake was not an isolated event. It was part of an escalating seismic sequence on the Noto Peninsula that had been building since at least 2020, when a swarm of small earthquakes began rattling the region. A shindo 6-lower quake struck in June 2022. The May 2023 event raised the intensity further. Then, at 4:10 p.m. on January 1, 2024, a magnitude 7.5 earthquake -- the most powerful to strike the peninsula in modern records -- ruptured more than 150 kilometers of fault. The shaking reached shindo 7. The coastline shifted. Parts of the peninsula rose nearly four meters. More than 700 people died, over 200,000 structures were damaged, and the cities of Suzu, Wajima, and Anamizu were devastated. The 2023 quake had been a warning shot. The peninsula had been speaking, but no one could have known what it was building toward.