Phivolcs, JICA to revisit study on 'The Big One'

The Philippine government and the Japan International Cooperation Agency (JICA) are currently in talks to revisit next year the 2004 study on the impact of "The Big One" or magnitude 7.2 earthquake in Metro Manila.

- By EMMANUEL TUPAS

“We have no idea yet when in 2026, but definitely it will start next year,” Philippine Institute of Volcanology and Seismology director Teresito Bacolcol said at the Saturday News Forum in Quezon City yesterday.

The 21-year-old study projected the fatalities in Metro Manila, which then had a population of 9.9 million, to be as high as 33,500 alongside 113,600 injured. When nearby provinces are included, the death toll could reach 48,000.

“The Big One” is a scenario of a massive earthquake in the event the Marikina Valley fault system, which extends from Doña Remedios Trinidad in Bulacan to Canlubang in Laguna, moves.

Bacolcol said the study needs to be revisited since a lot has happened in Metro Manila in the past 21 years.

“The population of Metro Manila grew and there are a lot of new buildings, so we really need to revisit the study,” he noted.

He said the new study will be completed in two years.

"We are just waiting for some signatures but next year we will start," he said.

Meanwhile, Bacolcol said "The Big One" could also trigger the eruption of Taal Volcano in Batangas.

Asked for the possible impact, he said it might be similar to the major eruption of Taal in 2020.

Better detection

With the fault responsible for the powerful magnitude 6.9 earthquake in Cebu now identified, Phivolcs said it is working to overcome obstacles in determining offshore active faults.

The bureau has named it the Bogo Bay Fault, with its inland extension located at Sitio Looc in Barangay Nailon, Bogo City.

Phivolcs' field investigation found open cracks, fault scarps and small pressure mounds in the area, suggesting the fault may extend up to 1.5 kilometers.