MANILA—Potentially deadly landslides are still possible from aftershocks of last week’s magnitude 6.7 earthquake off Surigao del Norte province.
“Aftershocks that are strong enough can trigger such landslides there,” said geologist Bryan Marfito from State-run Philippine Institute of Volcanology and Seismology (Phivolcs).
He said Surigao del Norte’s western portion is susceptible to landslides due to its hilly terrain so communities there must prepare accordingly.
“Slope stability there is low unlike in Surigao del Norte’s central and eastern portions which are mainly lowlands,” he noted.
West-lying San Francisco and Malimono municipalities are among the province’s most landslide-prone areas, he said.
Landslides can also occur in Surigao del Sur province if the aftershocks are strong enough and near that area, Marfito continued.
“Heavy rainfall can likewise trigger landslides in Surigao,” he said.
Marfito said Phivolcs hasn’t yet received reports of landslides directly triggered by the 10:03 p.m. earthquake off Surigao del Norte last Friday (Feb. 10).
He, however, noted that communities in Surigao del Norte must still be alert to possible landslides as Phivolcs monitoring so far shows the earthquake’s aftershocks are still concentrated in this province.
“Avoid elevated areas as much as possible,” he urged people there.
Phivolcs reported already monitoring, as of 9 a.m. Monday (Feb. 13), 151 aftershocks from the Surigao earthquake.
Six of those aftershocks were reported felt, said Phivolcs science research analyst Wilmer Legaspi.
He noted some of the aftershocks occurred at depths deeper than the 11 kms Phivolcs reported for Friday’s earthquake.
Several aftershocks were also moderately strong as these ranged from magnitude 4.0 to 4.9, Phivolcs data show.
In its latest available situation report this week, National Disaster Risk Reduction and Management Council (NDRRMC) said Friday’s earthquake affected almost 5,200 people in Surigao del Norte.
Eight persons were reported dead due to that earthquake while 202 people sustained injuries, noted NDRRMC.
NDRRMC also said the earthquake damaged school facilities, an airport runway, a hospital, roads, bridges and around 1,034 houses in Surigao del Norte.
San Francisco, Malimono and other municipalities in Surigao del Norte experienced total blackout and water service interruptions due to the earthquake, NDRRMC further reported.
Authorities already placed Surigao del Norte’s capital Surigao City under a state of calamity.