The Central Weather Administration said the tremor on Monday originated in eastern Hualien, the region which was the epicenter of the earthquake that hit Taiwan on April 3
Taipei, April 22 (CNA) Five earthquakes ranging from magnitude 4.4 to 5.5 shook eastern Taiwan in rapid succession late Monday afternoon, continuing the unsettling roller coaster ride Hualien County residents have been on since a magnitude 7.2 earthquake hit the county on April 3.
The biggest of the series, a magnitude 5.5 quake that hit at 5:08 p.m. Monday, occurred first in Hualien County’s Shoufeng Township 26.8 kilometers south-southwest of Hualien County Hall at a depth of 10 km, according to the Central Weather Administration (CWA.)
The earthquake’s intensity, which gauges the actual effect of a seismic event, was highest in Hualien and Nantou Counties, where it measured a 4 on Taiwan’s 7-tier intensity scale, but it was felt across much of Taiwan.
A magnitude 4.4 temblor centered in the township occurred a minute later at a depth of 9.5 km, and also reached an intensity level of 4 in Hualien County and 2 in Nantou County to the west and Yilam County to the north.
That was followed by rapid fire earthquakes of magnitudes 5.3, 4.9, and 4.9 temblors at 5:12 p.m., 5:15 p.m. and 5:17 p.m., again centered in Shoufeng Township, CWA data showed.
They were all relatively shallow, occurring at depths of 10 kilometers, 5.4 km and 2.8 km respectively.
Each one generated an intensity level of 4 in Hualien County, described as shaking that leaves people frightened and even looking for shelter while toppling unstable objects.
Wu Chien-fu, director of the CWA’s Seismological Center, said at a press briefing in Taipei that the series of shallow quakes were aftershocks of the April 3 earthquake.
He said an earthquake of a magnitude of 5 and above usually generates two to three weeks of aftershocks, but they will last longer after the magnitude 7.2 earthquake as underground stresses continue to be released.
Wu noted that the frequency and number of aftershocks have generally abated, despite Monday’s activity, but he expected that more aftershocks are to come, mostly of magnitude 3 and occasionally magnitude 4.
From April 3 to April 22, there have been 935 mainshocks and aftershocks, including the 7.2 magnitude earthquake, with two over magnitude 6, 37 of magnitude 5-6, 274 of magnitude 4-5, and 621 of magnitude 3-4, according to Wu.
The Hualien County Fire Department said late Monday afternoon it had not received any immediate reports of injuries or damage following the aftershocks.
Additionally, after the first series of five earthquakes occurred, another earthquake of magnitude 5.1 occurred in Shoufeng Township at 5:53 p.m. followed by a magnitude 4.4 quake a minute later and a magnitude 4.3 quake another 15 minutes later.
The magnitude 7.2 earthquake that rocked Taiwan on April 3 has left at least 17 people dead and more than 1,100 people injured.
