A 7.2 magnitude earthquake centered off Taiwan's eastern coast on Wednesday morning was widely felt throughout the island and was followed by over 100 aftershocks throughout the day. 

"I thought I was going to die," a 30-year-old Taipei resident told DW, describing the fear she experienced as her apartment violently shook.

An elementary school teacher in New Taipei City said she was with her pupils at the playground when the ground started to shake. "It was the first time I felt the entire crust behaving like a spring," she told DW.

As of Thursday morning, authorities said there have been at least nine deaths and over 1,000 injuries, with Hualien County in eastern Taiwan suffering the most serious damage and casualties.

Several key routes to Hualien have been closed due to landslides, and many buildings in the region have severely tilted or collapsed. Rescue workers were continuing their efforts to save those who remained trapped.

Lessons learned from the '921' earthquake

The tremor was Taiwan's strongest since a 7.3-magnitude earthquake struck the central part of the island in 1999.  

It caused over 2,000 fatalities, around 11,300 injuries and the complete collapse of more than 51,000 buildings.

Named after the date it happened, September 21, 1999, the tragic event is widely known in Taiwan as the "921" earthquake.

However, compared to the 921 earthquake, the recent tremor has resulted in less damage and fewer fatalities.

Ou Yu-chen, director of the Center for Earthquake Engineering Research at National Taiwan University, attributed this to "substantial progress in construction and design-related technologies." 

In severe earthquakes, the collapse of buildings is usually the main cause of casualties and injuries. Since the 921 tremor, newly constructed buildings in Taiwan have become "increasingly earthquake-resistant," Ou told DW.

Improvements were made in designing buildings to withstand stronger earthquakes, including incorporating more elasticity in buildings.

"When designing buildings, we typically assume a certain seismic intensity. Now, we've elevated that scale to enable the structures to withstand stronger earthquakes," Ou said.

"Elasticity means that even if an earthquake exceeds the structure's capacity, the building may sway, sustain damage and develop cracks, but it's less likely to collapse," he added.

Taiwan sits on an arc of intense seismic activity

However, officials responsible for disaster response after the recent quake said the offshore location of the epicenter played a major role in limiting damage. 

A staffer of Taiwan's Central Emergency Operation Center (CEOC), who spoke on condition of anonymity, told DW that the 921 earthquake caused more significant damage because its epicenter was on land and at the center of the island.

Wednesday's quake struck off the less populated eastern coast of the island.

In 2018, a tremor also hit Hualian in a similar way and led to 17 deaths.

Taiwan sits on a boundary of tectonic plates and has experienced numerous earthquakes throughout history. Its population is rather accustomed to frequent seismic activity.

But the CEOC staff member said that official and public awareness regarding preparedness for major earthquakes is crucial, adding that quake preparedness has long been "a cornerstone of disaster education campaigns."

"We've also been continuously helping local governments to build the response capabilities, including how to swiftly engage in disaster relief when an earthquake strikes."

But despite Taiwan's disaster preparedness with a robust early-warning system, many people complained that they did not receive official alerts on their phones when the violent shakes began on Wednesday.

Authorities later explained that a relatively mild earthquake was expected, and that's why they did not send out warnings.

Strong aftershocks expected

Taiwan continued to feel aftershocks on Thursday. Officials also warned there could be over 7-magnitude tremors in the coming days.

In some cases, the first major quake can occur before an even stronger tremor. In the 2018 Hualien earthquake, the main tremor occurred two days after a strong 5.8 quake mistaken as the main one with a series of aftershocks.

Chang Wen-Yen, an environmental science professor at Taiwan's National Dong Hwa University, told CommonWealth Magazine that local governments across the island should expedite the inspection of the seismic resistance of older structures — especially since the strong quake may have weakened some building structures.

"Just because they didn't collapse this time doesn't mean they won't collapse next time," Chang told the local magazine.

Edited by: Srinivas Mazumdaru