Continued aftershocks expected after 4 quakes shake southern Taiwan

Taipei, Dec. 12 (CNA) More aftershocks may occur in southern Taiwan following four consecutive earthquakes that shook the area on Thursday night and early Friday, the Central Weather Administration (CWA) warned Friday.

Three quakes hit Kaohsiung's Jiasian District late Thursday night at 10:49 p.m., 10:59 p.m. and 11:19 p.m., registering magnitudes of 4.7, 3.5 and 4.7, at depths between 8 and 8.2 kilometers, according to CWA data.

A fourth quake of magnitude 4.0 hit the nearby Nansi District in Tainan at a depth of 8.9 kilometers at 4:24 a.m. Friday.

The first, third and fourth earthquakes recorded intensity levels of 4 on Taiwan's 1-7 intensity scale, but mostly in mountainous, relatively sparsely populated areas.

The intensity level gauges the actual degree of shaking at a particular location. A level 4 shake is strong enough to wake people up and cause unstable indoor items to fall.

Chiu Chun-ta (邱俊達), a section chief at the CWA Seismology Center, said the Jiasian quakes were extremely shallow, causing residents near the epicenters to feel strong shaking.

The quakes were caused by stress adjustments along the boundaries of the Philippine Sea Plate and Eurasian Plate, which generate tectonic forces that pull in different directions near the epicenters, making the area geologically complex and fragile, Chiu said.

Chiu said the quakes are part of stress readjustments following the Jan. 21 Dapu earthquake, and that smaller earthquakes may continue in the coming days as nearby faults release accumulated stress.