Another earthquake–Magnitude 6.8–hits offshore Manay, Davao Oriental

A magnitude 6.8 earthquake struck off the shore of Manay, Davao Oriental, at 7:12 p.m. on Friday evening, the Philippine Institute of Volcanology and Seismology (PHIVOLCS) said. 

LIVE UPDATES: Davao Oriental earthquake

It was initially reported as magnitude 6.9, but it was later downgraded. This quake came after the offshore magnitude 7.4 earthquake that also struck Manay earlier in the day. 

A tsunami warning was also issued, recommending immediate evacuation in the coastal areas of Surigao del Sur, Davao Oriental, and Surigao del Norte.

A map released by the Office of Civil Defense showed at least 1.8 million people live in these coastal communities.

PHIVOLCS lifted the tsunami warning at 11:12 p.m. Friday after its sea level monitoring stations in Bislig City and Tandag City in Surigao del Sur did not detect "any significant tsunami waves." 

The following intensities were reported in the areas below: 

Intensity VI - Manay, Davao Oriental 

Intensity V - Baganga, Boston, Caraga, Cateel, and Tarragona, Davao Oriental 

Intensity IV - Mawab, Monkayo, Nabunturan, and Pantukan, Davao de Oro; City of Davao; City of Mati, Davao Oriental; City of Bislig, Surigao del Sur 

Intensity III - Abuyog, City of Baybay, Dagami, Dulag, Javier, Julita, Leyte, Macarthur, Mahaplag, Mayorga, Palo, Santa Fe, Tabontabon, Tanauan, and Tolosa, Leyte; City of Tacloban; Hinunangan, Pintuyan, San Francisco, San Juan, San Ricardo, Silago, and Sogod, Southern Leyte; City of Digos and Magsaysay, Davao del Sur; City of Kidapawan, M'lang, Makilala, and President Roxas, Cotabato; Lambayong, Sultan Kudarat; Cagdianao, Libjo, San Jose, and Tubajon, Dinagat Islands

Intensity II - City of Borongan, General Macarthur, and Hernani, Eastern Samar; Palapag, Northern Samar; City of Cagayan De Oro, City of Cagayan de Oro; Alamada, Antipas, Banisilan, Kabacan, Magpet, and Matalam, Cotabato; Columbio, Esperanza, Isulan, Kalamansig, Lebak, Lutayan, President Quirino, Senator Ninoy Aquino, and City of Tacurong, Sultan Kudarat

Intensity I - Molave, Zamboanga del Sur; Carmen, and Pigkawayan, Cotabato 

PHIVOLCS warned of damage and aftershocks.

‘Doublet earthquake’ 

With two strong earthquakes hitting offshore of Manay on the same day, PHIVOLCS explained that these could be considered “doublet earthquakes.” 

“They are distinct or different earthquakes in almost the same area with two (or more) main shocks that have a slight difference in magnitude,” the state seismologists said. 

“This happens when faults or trenches are causing the stress to trigger a sequence of events,” it added. 

PHIVOLCS earlier noted that the magnitude 7.4 earthquake in the morning was triggered by the movement in the Philippine Trench. 

Further, PHIVOLCS said that it is “continuously analyzing the earthquake parameters to further characterize these earthquake events.” –NB/VBL, GMA Integrated News