MANILA, Philippines — A powerful magnitude 7.4 earthquake jolted Surigao del Sur at 10:37 p.m. on Saturday, Philippine Institute of Volcanology and Seismology (Phivolcs) director Teresito Bacolcol said, expecting damage to infrastructure.
At least one casualty was reported.
At a press conference yesterday, Bacolcol said Phivolcs initially recorded the strength of the quake as magnitude 6.9, but it was upgraded to magnitude 7.4 after gathering more data.
“Last night (Saturday) we also issued a tsunami advisory. It was lifted at 3:23 this morning,” he said.
A tsunami warning as high as one meter was issued for all coastal communities in Surigao del Sur and Davao Oriental, where immediate evacuation was recommended in the affected areas.
“There were confirmed tsunami occurrence. The highest was 0.64 meters in Mawes Island in Hinatuan; 0.18 meters in Lawigan, Bislig City; 0.05 meters in Port of Dapa, Surigao del Norte; and 0.08 meters in Mati, Davao del Oriental. So, it did not reach the one meter tsunami range,” he said.
Phivolcs said that the last recorded wave arrival in the Philippines occurred at 2:52 a.m. at Hinatuan-Bislig Bay Station in Mawes Island yesterday.
In Malacañang, President Marcos assured communities hit by the earthquake that efforts are underway to assist them and to ensure their safety.
“We continue to provide assistance to the families affected by the impact and aftermath of the magnitude 7.4 earthquake in Mindanao,” Marcos said in a post on X yesterday.
“The DSWD (Department of Social Welfare and Development) and DILG (Department of the Interior and Local Government), in collaboration with local government units, are actively coordinating efforts to provide essential aid to those in need.”
The public works department is “diligently” assessing the Caraga region with the support of the Office of Civil Defense and National Disaster Risk Reduction and Management Council, the President said.
Officials of the Police Regional Office-13 (PRO-13) and the Caraga Regional Disaster Risk Reduction and Management Office stated in separate reports that the earthquake forced villagers in coastal areas to move to higher ground due to a possible tsunami.
“There is no more risk (of tsunami). Our advisory of the expected tsunami was until close to midnight and, as of now, it is no longer in effect,” Bacolcol added.
PRO-13 director Brig. Gen. Kirby John Kraft said all of their police units in Agusan del Sur had been mobilized to help local government units (LGUs) reach out to affected villagers and respond to any emergency.
Defense Secretary Gilbert Teodoro, in a press briefing in Camp Aguinaldo, Quezon City, reported that there was one dead from the earthquake, with four injured.
“As of this time, there are 529 families affected, 2,647 persons. There is one dead, unfortunately – she was a pregnant lady. Four injured,” Teodoro said.
Bacolcol said that the epicenter of the magnitude 7.4 quake was located 30 kilometers north of Hinatuan, Surigao del Sur, tectonic in origin and with a depth of focus of 25 kms.
“The epicenter of the earthquake was in the ocean and the source was the Philippine Trench,” Bacolcol added.
He said other strong quakes were recorded in Mindanao due to the movement of the Philippine Trench.
“The Philippine Trench is very active. There are minor movements every now and then,” Bacolcol elaborated, citing strong quakes caused by the trench recorded in 1921 (magnitude 7.5, with tsunami), 1929 (magnitude 7.2), 1952 (magnitude 7.6) and 1992 (magnitude 7.1), all in the Maguindanao area close to the epicenter of Saturday evening’s earthquake.
As of 1 p.m. yesterday, at least 819 aftershocks had been recorded , with magnitudes of 1.4 to 6.2, of which 171 were plotted and at least 10 were felt.
“The aftershocks would last for several days to several weeks. The magnitude of the aftershocks would decrease in number and would also decrease in magnitude,” Bacolcol said.
He noted that the magnitude 7.4 in Surigao del Sur was not connected with the magnitude 6.8 earthquake in Sarangani, Davao Occidental on Nov. 17, as the latter was caused by the Cotabato Trench.
Preliminary damage report
“Magnitude 7.4 is classified as destructive, so we would expect damage to infrastructure. In fact, we already received a report that a bridge was damaged in Surigao del Sur. We are still confirming this. So far, based on the initial report, the ceiling of a house also collapsed,” Bacolcol said.
The defense secretary added that two bridges have been closed temporarily due to quake damage – the Matina bridge and Bolton bridge. “Power has been restored in all areas,” Teodoro added.
“There is a suspension of classes in the province of Davao del Norte and we expect the LGU, after their assessment, will be the ones to determine whether or not there will be any suspension of classes on Monday,” he said in a mix of Filipino and English.
He said that the DSWD was on the ground to provide shelter facilities as well as aid to affected persons and families.
The Philippine Ports Authority reported yesterday that minor cracks were discovered at the operational area of Lawigan Port in Surigao del Sur.
Meanwhile, the Civil Aviation Authority of the Philippines (CAAP) reported no damage to Mindanao airports.
In the initial report by Area 12 manager Evangeline Daba, only minor damage was seen at Butuan, Surigao, Siargao, Tandag and Bislig airports.
CAAP-Davao Area 11 Manager Rex Obcena said that except for a few wall tiles that fell off near the international arrival elevator, all Davao International Airport vital facilities did not incur damage. Passengers and duty personnel were declared safe.
Phivolcs reported that intensity 7 was recorded in Tandag City, Surigao del Sur; intensity 6 in Bislig City, Surigao del Sur; and intensity 5 in Cagayan de Oro City; Nabunturan, Davao de Oro, and Davao City.
Intensity 4 was felt in Duero and Garcia Hernandez, Bohol; Mandaue City; Alangalang, Baybay City, Burauen, Dulag, Hilongos, Jaro, Javier, Julita, La Paz, Macarthur, Mahaplag, Mayorga, Palo, Pastrana, Santa Fe, Tanauan and Tolosa, Leyte; Tacloban City; Anahawan, Bontoc, Hinunangan, Hinundayan, Liloan, Limasawa, Malitbog, Padre Burgos, San Francisco, San Juan, Silago and Sogod, Southern Leyte; Alabel and Malungon, Sarangani; Tupi, South Cotabato; and Surigao City, Surigao del Norte.
Intensity 3 was felt in Tagbilaran, Bohol; Leyte, Leyte; Dapitan City, Zamboanga del Norte; Molave, Zamboanga del Sur; San Fernando, Bukidnon; Kidapawan City, Cotabato; Glan, Kiamba, Maasim and Malapatan, Sarangani; Banga and Koronadal City, South Cotabato; General Santos City; President Quirino, Sultan Kudarat; Datu Odin Sinsuat and Sultan Kudarat, Maguindanao, and Cotabato City.
“If we see visible cracks in our homes, don’t go inside as a strong aftershock could cause damage. It is better to consult our municipal or city engineer,” Bacolcol said.
Science and Technology Secretary Renato Solidum Jr., said that the magnitude 7.4 earthquake that shook Surigao del Sur was unquestionably a “Big One,” the sort that Metro Manila should thoroughly prepare for.
In a message to The STAR, Solidum said, “Magnitude 7.4 is a major earthquake.”
He said that Phivolcs and the Department of Science and Technology have been watchful of a major earthquake from the Philippine Trench.
“The Philippine Trench east of Mindanao and Visayas was expected to generate a major earthquake and cause a tsunami. That is why these areas were prioritized for earthquake and tsunami preparedness as part of the multi-agency Ready project before,” Solidum said. — John Felix Unson, Rainier Allan Ronda, Evelyn Macairan, Rudy Santos, Alexis Romero, Delon Porcalla