Japan’s deadliest fault line shifts, frustrating megaquake forecasts

A recent Japanese study has revealed that the locked zone along the Nankai Trough, a major fault line off Japan's Pacific coast, is not static but changes over time. This discovery complicates efforts to predict megaquakes in the region. The Nankai Trough is where the Philippine plate subducts beneath the Eurasian plate, with the Philippine plate moving at a rate of 4-6 cm per year. Locked zones are areas where tectonic plates merge, allowing stress to accumulate before being released as an earthquake. The dynamic nature of these locked zones presents a significant challenge for forecasting seismic events.