A magnitude 6.1 earthquake struck off the coast of Yilan County at 5:50 Thursday morning. It was followed by three aftershocks in the next six minutes, ranging up to magnitude 5.2. No injuries or deaths were immediately reported.

Wu Chien-fu
CWB Seismology Center
Taiwan is located where the Eurasian and Philippine Sea tectonic plates converge. Over here in Hualien, one plate has been sliding below another as it moves northeast. So in April, May, June and July, there were many shallow earthquakes in Hualien. This area belongs to Taiwan’s east seismic belt. The epicenter of the earthquake at 5:50 a.m. was situated in the Okinawa Trough. The cause was the subduction of the Philippine Sea Plate as it moved northeast. As it sank under, it created an island arc, with a back-arc basin. The earthquake today, we think it happened due to an expansion of the back-arc basin. This area is part of one of Taiwan’s seismic belts, the northeast seismic belt. About 70% of the earthquakes in Taiwan occur here.

The seismologist says that on average, Taiwan experiences two to three earthquakes greater than a magnitude 6. This latest temblor is the third one this year. He says that aftershocks of up to magnitude 5 are likely over the next two weeks.