Study finds Tongan volcano caused 700‑metre seafloor drop in minutes

An underwater volcano off Tonga caused the sea floor to plunge about 700 metres in just a few minutes, a new scientific study reports. The rapid collapse was detected by seismic and satellite measurements that showed a sudden shift in the ocean bottom. Researchers say the event was triggered by the volcano’s explosive eruption, which destabilized the overlying sediment layers. The study, published by an international team of geologists, highlights how such fast‑moving landslides can generate large tsunamis and disrupt marine ecosystems. The findings come months after the massive January eruption that sent shockwaves around the globe, but this latest work focuses on the hidden danger beneath the water. Experts warn that monitoring of volcanic islands needs to include deep‑water surveys to catch similar rapid movements. The report adds to growing evidence that volcanic activity in the Pacific can reshape the seafloor in seconds.