What is this crater-like formation that was spotted in Davao City?

A crater-like formation in Davao City has become a curiosity online after airplane passenger took a photo of it midflight.

According to an episode of “Kapuso Mo, Jessica Soho,” the photo was taken by Frank Yves Pacatang, who frequently flies between Cebu and Davao.

The image shows what seems to be a crater covered with trees and plants. Pacatang learned from a commenter that its location is in Barangay Bato in Toril, Davao City.

The KMJS team visited the area and was greeted by a cliff. A restaurant overlooking the landscape sits on the edge of it [cliff]. According to Eduardo Comidoy, a resident of the area, people live  on the ridge and basin of the crater.

Water is abundant, so residents plant rice, vegetables, and fruits for their livelihood. Comidoy’s family, meanwhile, owns a swimming pool that they rent out to holidaymakers.

“Ang tubig sa pool namin ay nagmula sa paligid lang. Merong bumubulwak na tubig diyan, kahit saan,” he said.

(“The water in our pool just comes from around here. Water just sprouts anywhere.”)

When heavy rain falls, the water level gets very high and sometimes landslides occur. Huge noises also echo in the area.

What could the “crater” be?

“You can have ‘yung mga sinkhole pero ‘yun kasi, mostly mga carbonate rocks. Pwede rin ‘yung mga impact craters,” said Jyreen Penaloga from Department of Environment and Natural Resources - Mines and Geosciences Bureau.

“Pero so far, wala naman silang nakitang mga old parts ng meteorites. So the only possible is isa siyang very, very old volcanic feature,” she said.

(“It’s possible that it’s a sinkhole but mostly it’s just carbonated rocks. It can also be an impact crater. But so far, they have not found old parts of meteorites. So the only possibility is it’s a very, very old volcanic feature.”)

Penaloga said the area is not listed under active volcanoes or potentially active volcanoes.

Valerie Shayne Olfindo, a research specialist at the Philippine Institute of Volcanology and Seismology, said the landscape is a low-relief volcanic crater or Maar. It is a low volcano that is formed due to phreatomagmatic eruption.

“‘Yung Banud crater po ay hindi kagaya ng Pinatubo at Taal na merong continuous na supply ng magma sa ilalim. Usually crater lake 'yung nafo-form,” she said.

“Hindi po dapat mabahala ang mga residente na malapit sa Banud crater dahil napakababa po ng posibilidad na pumutok.”

(“The Banud crater is not like Pinatubo and Taal which have a continuous supply of magma underneath. Usually what is formed is a crater lake. The residents don’t have to worry because there is a very very low chance of eruption.”)

Residents in the area, however, are thankful to be aware of the possible dangers, however small.

Barangay captain Alfredo Cabreros said they will be ready to evacuate the residents in case an emergency situation arises.

“Siguro kapag mapatunayan, susunod kami sa utos ng gobyerno na lilikas kami. Pero kasi wala itong mga sulfuric element na makikita since bata pa ako,” Comidoy said.

(“If it’s proven [to be a danger], we will follow the government’s order to evacuate. But there has not been a sulfuric element found here since I was a child.”)

—MGP, GMA News