On 3 April 2024, at 07:58:11 NST (23:58:11 UTC on 2 April), a 7.4 earthquake struck south of Hualien City, Hualien County, Taiwan. At least 19 people were killed and over 1,100 were injured in the earthquake. It was the strongest earthquake in Taiwan since the 1999 Jiji earthquake, with three aftershocks above Mw 6.0.
Tectonic setting
Taiwan has a history of strong earthquakes. The island is located within a complex zone of convergence between the Philippine Sea plate and Eurasian plate. At the location of the earthquake, these plates converge at a rate of per year. To the south of Taiwan, oceanic crust of the Eurasian plate is subducting beneath the Philippine Sea plate creating an island arc, the Luzon Arc. At Taiwan, the oceanic crust has all been subducted and the arc is colliding with continental crust of the Eurasian plate. To the north of Taiwan, the Philippine Sea plate is in contrast subducting beneath the Eurasian plate, forming the Ryukyu Arc.
Earthquake
Taiwan's Central Weather Administration (CWA) measured the earthquake's local magnitude at 7.2, while the United States Geological Survey (USGS) placed the earthquake at 7.4. It was the strongest earthquake to hit Taiwan since the 1999 Jiji earthquake, which measured 7.7.
At least 1,400 aftershocks were recorded following the earthquake. A 6.4 aftershock struck at 00:11 UTC, followed by a 5.6 event at 00:35, a 5.3 at 00:43 and a 5.6 at 00:46. On 22 April, a 5.8 event struck at 14:11, followed in the evening (early morning of 23 April NST) by two large aftershocks that occurred south of Hualien City, both of them measuring 6.1. A 5.7 aftershock occurred near Taroko National Park on 26 April.
The earthquake had a maximum CWA seismic intensity of 6+ in Hualien City and 5- in Taipei. Intensity 4 or higher was felt across much of the island except its southern extent, which felt intensities 2 to 3. At Taroko National Park, a maximum peak ground acceleration of 1,491.14 gal (1.52 g) was recorded by a CWB station. In China, shaking was felt in Shanghai, Suzhou, Shenzhen, Guangzhou, Shantou, and parts of Fujian, Zhejiang, and Jiangsu provinces. It was also felt in Hong Kong and on the island of Yonaguni, Japan, where it measured Shindo 4 on the Japan Meteorological Agency seismic intensity scale.
The earthquake had a focal mechanism corresponding to reverse-faulting at a depth. According to the USGS, the rupture occurred on a northeast–southwest-striking, moderately dipping, reverse fault within the Eurasian plate. The estimated rupture dimensions for a similarly sized reverse-faulting earthquake is by . Its finite fault model indicated rupture on an east-southeast dipping plane. The slip occurred within an elliptical rupture area by on the plane. The maximum displacement was estimated at . The shock's magnitude was identical to a 1986 earthquake that killed 15 people in Hualien.
The China Earthquake Administration (PRC) estimated the earthquake rupture process did not exceed 35 seconds in duration. The slip was distributed across a fault. According to their finite fault model, slip was mainly concentrated around the epicenter, reaching of maximum displacement. The model's geometry consists of a northeast striking fault dipping at a shallow angle to the northwest. About of slip occurred at the shallow part of the fault that reaches the seafloor off the island's coast. As of November 2024, Hualien City was still experiencing aftershocks.
Tsunami
A tsunami was triggered by the earthquake, with a maximum height of in parts of Hualien City. A wave was observed in Chenggong, Taitung, while an surge was recorded in Wushi Harbor. The CWA issued an alert advising residents to evacuate to higher ground. The Ministry of Natural Resources of the People's Republic of China issued a second-highest level orange tsunami alert, warning of potential localized waves that could cause significant damage in affected coastal areas.
In the Philippines, evacuations were ordered by the National Disaster Risk Reduction and Management Council in the provinces of Batanes, Cagayan, Isabela and Ilocos Norte following a warning by the Philippine Institute of Volcanology and Seismology (PHIVOLCS). An advisory was issued to 23 provinces for "high tsunami waves" measuring , which was later reduced to . At 10:03 (NST), the Pacific Tsunami Warning Center said "the tsunami threat has now largely passed", prompting PHIVOLCS to cancel the tsunami warning.
The Japan Meteorological Agency issued a tsunami warning for Okinawa Prefecture and as waves of were expected, which was later downgraded to a "tsunami advisory". A wave was observed at Yonaguni about 15 minutes after the earthquake. Waves were also expected along the Miyako and Yaeyama Islands, with -waves reaching the islands of Miyako-jima and Ishigaki. The tsunami warning was the first to be issued in Okinawa Prefecture since the 2011 Tōhoku earthquake and tsunami, while the tsunami was the first to strike the area since 1998. These warnings prompted flight suspensions in Okinawa and Kagoshima Prefectures; evacuations to the third floors were held at Naha Airport and Miyako Airport. The Japan Self-Defense Forces ordered its air assets at Naha Air Base to fly out or be moved to secure hangars or higher ground to prevent its possible destruction. China's Tsunami Warning Centre, which is under the Ministry of Natural Resources, issued its highest alert level at level 1, or red.
Impact 3 April
Eighteen fatalities were initially reported, along with a total of 1,145 people injured and 442 others initially declared stranded. Two people were listed as missing, namely a couple carrying dual Australian and Singaporean nationality. In December 2024, a court in Hualien issued death certificates for the two missing, while the remains of one of them were found in January 2025. The National Fire Agency recorded at least 1,151 earthquake-related incidents.
All fatalities occurred in Hualien County; most of the dead were killed in Taroko National Park, including ten hikers who were caught in rockfalls on Dekalun Trail, Xiaozhuilu Trail, and Shakadang Trail. This also included five members of the same family. Five people died after rockfalls occurred along the Central Cross-Island Highway and the Suhua Highway, while two fatalities occurred inside mining areas of Xiulin after rockfalls. A woman in Hualien City died after she returned to her building to retrieve her cat, during which she was pinned down by a column following an aftershock. Five cats trapped in the building, including the deceased woman's cat, were later found alive and were rescued.
Taiwan's earthquake alert system did not send an advance alert of the mainshock, unlike in previous instances. Authorities later said that they had initially estimated the earthquake to be of a smaller magnitude ranging between 6.2 and 6.8. The CWA Seismology Center later clarified that it had sent out two alerts that covered the immediate area of the epicenter as well as parts of southern and central Taiwan but not the Taipei area, adding that conditions for issuing a national-level warning depended on the earthquake measuring a magnitude above five and its intensity reaching four on the CWA's seven-level scale.
Six hundred people were stranded in Taroko National Park. Twelve park visitors, including two Canadian nationals, were stranded along a trail, while 40 others were injured. Injuries were also reported across Hualien City, Yilan, Taipei, New Taipei City, Keelung, Taichung and Taoyuan due to falls or toppled objects. Sixty people were trapped inside the Jinwen Tunnel along the Suhua Highway, while 50 employees of the Silk's Place Hotel Taroko who were traveling in four minibuses were also declared trapped after none of them could be contacted by authorities over the phone. The hotel management later said that the employees were safe, citing three staff who had reached the hotel on foot. A rescued employee later said that their convoy had been trapped in a tunnel following a rockfall and that the vehicle she was in was severely damaged by a rock. The road immediately outside the Qingshui Tunnel caved in, trapping several people inside. Seventy people were also trapped in two rock quarries, while nine people were trapped inside a cave.
The Central Emergency Operation Center reported at least 2,498 cases of damage nationwide following the earthquake, with 1,140 instances in Taipei, 497 in New Taipei and 366 in Hualien County. At least 111 structures were destroyed, while 1,939 houses, 870 buildings and 75 roads and tunnels were damaged by the earthquake. Of the 28 reported building collapses, 17 of them occurred in Hualien, while the other 11 occurred in Yilan, New Taipei and Keelung. Collapses trapped at least 20 people in the immediate aftermath. Twelve buildings deemed unsafe were ordered demolished by authorities. In Hualien City, two houses, the nine-story Uranus building and a restaurant collapsed, trapping many people inside. One person was found dead while 22 others were later rescued from the Uranus building, which was built in 1986 prior to the introduction of more stringent building codes in the wake of the 1999 Jiji earthquake and was found to be lacking supporting ground-floor front pillars. Forty-eight residential buildings in the city were damaged, and the National Hualien Girls' Senior High School also sustained heavy damage. At least 200 residents living near the epicenter were displaced. A total of 1,400 households in Hualien County were damaged.
In Taipei, 249 people were injured, six of them seriously, and 10 houses were severely damaged. A warehouse collapsed in New Taipei City, causing three minor injuries. Fifty people were subsequently rescued from the building. Tiles were dislodged and fell off older buildings and some newer structures in the capital. The Legislative Yuan building also sustained damage to its walls and ceilings, while debris fell from the Liberty Square archway of Chiang Kai-shek Memorial Hall. Subsidence in Xindian District caused seven houses to collapse, forcing 12 people to evacuate. A viaduct of the New Taipei Circular line between Banxin and Zhongyuan stations was disaligned, while a train was derailed at Jingan station, damaging the station platform and track bed. All service on the Taipei Metro was briefly suspended for safety checks. Nevertheless, train service through the epicenter region was restored within 24 hours. A portion of the ceiling in Taoyuan International Airport collapsed. Another 68 people were injured in Yilan City, where walls collapsed and water pipes ruptured. In Nantou County, 66 schools submitted disaster reports and nine residential homes sustained damage.
Power outages affected 371,869 homes in Taiwan according to the Ministry of Economic Affairs, of which, 14,833 were in Taichung; 5,306 were restored within approximately 25 minutes of the earthquake. Electricity was restored in 70 percent of households within two hours of the earthquake by Taipower, leaving around 91,000 homes without power. By the morning of 4 April, the number was reduced to 337. Water shortages affected 125,675 households, while outages of natural gas affecting 394 households and internet disruptions were also reported. Eighty cell phone base stations were damaged. There were reports of damaged walls, debris and toppled bricks across much of the island. High-speed railway services across Taiwan were partially suspended and major expressways in the eastern part of the island were closed. No anomalies were recorded in any of Taiwan's three nuclear plants.