Magnitude 5.5 quake strikes off Ilocos Norte

MANILA — A magnitude 5.5 earthquake struck the waters off Ilocos Norte on Tuesday morning, the Philippine Institute of Volcanology and Seismology (Phivolcs) said.

The tectonic quake hit 21 kilometers southwest of Pasuquin town at a depth of 43 kilometers.

Phivolcs initially measured the quake's magnitude at 5.8 and later downgraded it to 5.5. 

The undersea tremor was felt at Intensity 5 in Bacarra, Laoag, Pasuquin, and Vintar in Ilocos Norte; and Cabugao, Sinait, and Vigan in Ilocos Sur. 

This intensity causes "strong shaking and rocking" felt throughout buildings and could make hanging objects swing "violently", Phivolcs said. 

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It said the 10:38 a.m. was also felt in other areas at the following intensities. 

Intensity 4 - Batac, Paoay, and San Nicolas in Ilocos Norte; Banayoyo, Bantay, Caoayan, Magsingal, San Ildefonso, San Juan, Santa Catalina, and Santo Domingo in Ilocos Sur

Intensity 3 - San Isidro, Abra; Baguio City; Itogon, and La Trinidad, Benguet; Banaue, Ifugao; Bontoc, and Sagada, Mountain Province; Nagbukel, Narvacan, San Esteban, and San Vicente, Ilocos Sur

Intensity 2 - Alilem, Burgos, City of Candon, Cervantes, Gregorio del Pilar, Quirino, San Emilio, Santa, Santa Cruz, Santa Lucia, Santa Maria, Santiago, Sigay, Sugpon, Suyo, and Tagudin, Ilocos Sur

Intensity 1 - Galimuyod, Lidlidda, and Salcedo, Ilocos Sur 

The quake could spawn aftershocks, Phivolcs warned. 

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