Since the devastating 921 Earthquake hit the nation a decade ago, horizontal displacement, caused by the collision of the Earth’s tectonic plates, has occurred two to three times faster than previously in central Taiwan, including in Taichung County’s Sinshih (新社) Township and Nantou County’s Puli (埔里) Township, geologists say.
As Taiwan is located on the convergent boundary between the Eurasian Plate and the Philippine Plate, it has suffered from long-term collision of plates that have led to topographical changes. Academics say the fast changes in the crustal formation of Taiwan are proof that seismic activities are active, a warning that another major earthquake could occur.
Academics forecast that in 2500, a strong earthquake will likely occur in Nantou County’s Jiji (集集) Township, one of the worst-hit areas during the 921 Earthquake, and they are concerned that the next quake with a magnitude greater than 7.0 on the Richter scale will strike the Jianan Plain (嘉南平原).
PHOTO: AFP
Yu Shui-beih (余水倍), a researcher at Academia Sinica’s Institute of Earth Sciences says that Green Island and Lanyu on the Philippine Plate are moving closer to Penghu on the Eurasian Plate because of the compression resulting from the collision of the two plates. The Central Mountain Range has gradually been raised by the tectonic movement and energy accumulated in the earth’s crust.
Yu’s research team discovered that before the 921 Earthquake, a horizontal displacement of 1cm a year had been observed between Sinshih Township and the west coast, but that the displacement rate has increased between 3cm and 4cm a year since the quake occurred. To this day, the area has an accumulated horizontal displacement of 30cm and Sun Moon Lake has a displacement of 40cm.
Studies also show a horizontal shortening of 3cm a year in central Taiwan and a shortening of up to 4cm in southwestern Taiwan, while the East Rift Valley sees a steady shortening of 3cm a year.
Chen Wen-shan (陳文山), a professor of geology at National Taiwan University, said that a total of seven Paleo-earthquakes have been recorded at the Chelongpu (車籠埔) Fault in Taichung County over the past 3,000 years. A seismic analysis says the Chelongpu fault belongs to the time-predictable recurrence model and may experience a major temblor with a similar magnitude or higher than the 921 Earthquake again in around 400 years’ time.
Yu said, however, this does not mean that central Taiwan will not be struck by a quake with a magnitude of between 5 and 6 before then, so the public should remain vigilant.
A study by Yu showed that the Jianan Plain is one of the regions with a high risk of a strong earthquake. He said the next quake with a magnitude of 6.3 would be likely to occur in the Jianan Plain, Taipei, or central areas of the country, but since the exact time of the quake cannot be predicted, the public should take precautions against earthquakes at all times.
Wang Chien-ying (王乾盈), a professor of earth sciences at National Central University, said that two earthquakes that struck Chiayi County in 1792 and 1906 both measured 7.1 on the Richter Scale, killing thousands of people. In light of this, he is concerned that a strong earthquake may rattle Chiayi County about every 100 years.
In addition to conducting cooperation projects on earthquakes with the US and Japan, Taiwanese academics are also planning to work with China on artificial seismic sources to analyze seismic wave paths in the hope of getting a better understanding of the thickness and structure of the crust along the Taiwan Strait.
Both Yu and Chen said, however, that because of technology constraints, scientists still cannot predict when and where an earthquake will occur.
‘DENIAL DEFENSE’: The US would increase its military presence with uncrewed ships, and submarines, while boosting defense in the Indo-Pacific, a Pete Hegseth memo said The US is reorienting its military strategy to focus primarily on deterring a potential Chinese invasion of Taiwan, a memo signed by US Secretary of Defense Pete Hegseth showed. The memo also called on Taiwan to increase its defense spending. The document, known as the “Interim National Defense Strategic Guidance,” was distributed this month and detailed the national defense plans of US President Donald Trump’s administration, an article in the Washington Post said on Saturday. It outlines how the US can prepare for a potential war with China and defend itself from threats in the “near abroad,” including Greenland and the Panama
The High Prosecutors’ Office yesterday withdrew an appeal against the acquittal of a former bank manager 22 years after his death, marking Taiwan’s first instance of prosecutors rendering posthumous justice to a wrongfully convicted defendant. Chu Ching-en (諸慶恩) — formerly a manager at the Taipei branch of BNP Paribas — was in 1999 accused by Weng Mao-chung (翁茂鍾), then-president of Chia Her Industrial Co, of forging a request for a fixed deposit of US$10 million by I-Hwa Industrial Co, a subsidiary of Chia Her, which was used as collateral. Chu was ruled not guilty in the first trial, but was found guilty
DEADLOCK: As the commission is unable to forum a quorum to review license renewal applications, the channel operators are not at fault and can air past their license date The National Communications Commission (NCC) yesterday said that the Public Television Service (PTS) and 36 other television and radio broadcasters could continue airing, despite the commission’s inability to meet a quorum to review their license renewal applications. The licenses of PTS and the other channels are set to expire between this month and June. The National Communications Commission Organization Act (國家通訊傳播委員會組織法) stipulates that the commission must meet the mandated quorum of four to hold a valid meeting. The seven-member commission currently has only three commissioners. “We have informed the channel operators of the progress we have made in reviewing their license renewal applications, and
A wild live dugong was found in Taiwan for the first time in 88 years, after it was accidentally caught by a fisher’s net on Tuesday in Yilan County’s Fenniaolin (粉鳥林). This is the first sighting of the species in Taiwan since 1937, having already been considered “extinct” in the country and considered as “vulnerable” by the International Union for Conservation of Nature. A fisher surnamed Chen (陳) went to Fenniaolin to collect the fish in his netting, but instead caught a 3m long, 500kg dugong. The fisher released the animal back into the wild, not realizing it was an endangered species at
RSS