CNA file photo

Taipei, April 19 (CNA) Taiwan has been hit by 13 earthquakes of magnitude 5.0 or more so far this year, compared with an annual average of 24-25, the Central Weather Bureau (CWB) said Friday, after a magnitude 6.1 quake shook eastern Taiwan the previous day.

While the number is significantly higher than for the same period in other years, however, the CWB said it was within a reasonable range and did not necessarily indicate a higher frequency of earthquakes this year.

On average, Taiwan has 2-3 earthquakes of magnitude 6.0-7.0 and 22 of magnitude 5.0-6.0 each year, according to Wu Chien-fu (吳健富), deputy head of the bureau's Seismology Center.

"We do not have enough data to make the call that this situation has been abnormal," Wu said. "There could be months without any strong earthquakes later this year."

He was also unwilling to say if the higher number of relatively strong earthquakes resulted from a greater buildup of energy that has yet to be released, again pointing to the small sample size.

Wu did note that 70 percent of Taiwan's earthquakes are centered in northeastern Taiwan, but that the location of Thursday's temblor, the strongest so far this year, was relatively uncommon.

He said its epicenter was in an area with a geological formation of hard rock where the accumulation of energy is difficult.

"That region has recorded only six earthquakes measuring magnitude 5.0 or higher since the bureau began to keep records in 1973, including the one on Thursday," Wu said.

Wu said aftershocks of a similar level will be likely over the next week.

(By Lee Hsin-Yin)
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