Deadly Philippines quake turns seabed into shore

A powerful Philippine earthquake forced seafloor out of the water to make new shoreline.

Arsenio Butil Jr. fell to his knees and began to pray when last week's deadly 7.8-magnitude earthquake began shaking his home on the coast of the southern Philippines.

When he opened his eyes, he saw a once-familiar shoreline changing in real time, with swaths of previously submerged coral suddenly pushing above the waterline.

The June 8 quake, driven by a shifting of the nearby Cotabato Trench, toppled buildings, triggered landslides and killed at least 76 people on the southern island of Mindanao.

The tectonic forces at work also thrust chunks of the island's coastline upward in a phenomenon known as "coastal uplift," leaving stretches of shore unrecognizable to families who have spent their whole lives there.

During a visit to the area, AFP saw fishing boats that had once been at the water's edge on the wrong side of a wall of jagged, now-dead coral stretching for kilometers (62 miles) in both directions.

The tectonic forces thrust chunks of the Mindanao's coastline upward, leaving stretches of shore unrecognisable to families who have spent their whole lives there.

Butil, a fisherman and pastor living in Sarangani province's Glan, told AFP the June 8 quake was the largest that he had ever felt.

"The people were extremely panicked," he said.

"What I saw at the shoreline was that the water receded. After a while, I saw it ... slowly returning. And then it receded again. Maybe three or four times," Butil said.

"The fish were dying and floating."

The Cotabato Trench, which lies as close as 50 kilometers (31 miles) off Mindanao, is the site of frequent seismic activity, including a "swarm" of thousands of mostly small tremors recorded in January.

A U.N. disaster risk reduction report released in mid-May hinted they could be a precursor to a large earthquake.

"What they see now is their new coastline," Nane Danlag of the Philippines' seismology center told AFP from her office in General Santos City on Friday, adding the change was permanent.

The June 8 quake triggered landslides and killed at least 76 people on the southern island of Mindanao, and created new coastline.

"The (seabed) went up 2 meters," Danlag said, extending the shore by 200 meters (656 feet) in some areas according to initial assessments.

Pointing at a map, she said the affected area stretched between two towns nearly 100 kilometers (62 miles) apart.

As shocking as the changes to the coastline appeared, the shifting of the earth's crust that created it was a "natural movement," she said.

"This has been going on for thousands of years."

'What everyone fears'

In the hills above a neighboring village, about 100 men, women and children who fled to higher ground when the earthquake struck were still living in an encampment visited by AFP.

Datu Atom Malimpnig, a Maguindanaon chieftain, said the newly formed coastline had left the group of fishermen and their families hesitant to return to their now-destroyed homes.

Many remain convinced a tsunami could yet strike, he said, as government aid workers ladled rice porridge into bowls for the evacuees.

"(The seabed) rose ... It's not the same as it was before," Malimpnig said.

"What if the sea surges forward? That is what everyone fears," he said, adding their new home atop the hill felt far safer.

Ten kilometers (6 miles) away, Edzel Baylon, a staff member at the Isla Jardin del Mar resort, bemoaned a newly changed landscape that spelled trouble for a destination that touted a white-sand beach holiday experience.

"It has a huge effect on the resort, because the main draw for customers is the sea," she said, pointing at an idyllic beachfront now separated from the water by exposed coral.

"Sadly, today, our sea has become shallow. It's no longer suitable for swimming."

Since the June 8 quake, more than 8,500 aftershocks have shaken the region, according to the seismology agency.

In Glan, residents were thinking about next steps, but not yet ready to attempt to rebuild their destroyed homes, said Butil, the pastor.

"The ground there is cracked, and the cracks are long. That is why this area would be very dangerous if another earthquake as strong follows," he said.

Minutes later, a 5.4 tremor shook the ground underneath his feet.

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Deadly Philippines quake turns seabed into shore (2026, June 19)

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