Magnitude 6.4 quake rocks Abra, generates 368 aftershocks

MANILA – The Philippine Institute of Volcanology and Seismology (Phivolcs) stated that a magnitude 6.4 tectonic earthquake jolted Abra Tuesday night.

The quake hit around 9 km. northwest of Lagayan at 10:59 p.m. It was 11 km. deep.

Intensity VI was experienced in La Paz, Abra; and intensity V in Bangued, Boliney, Bucay, Bucloc, Daguioman, Danglas, Dolores, Lacub, Lagangilang, Lagayan, Langiden, Licuan-Baay, Luba, Malibcong, Manabo, Peñarrubia, Pidigan, Pilar, Sallapadan, San Isidro, San Juan, San Quintin, Tayum, Tineg, Tubo, and Villaviciosa, Abra; Conner, Apayao; La Trinidad, Benguet; Rizal, Kalinga; Alilem, Banayoyo, Bantay, Burgos, Cabugao, City of Candon, Cervantes, Galimuyod, Gregorio del Pilar, Lidlidda, Magsingal, Nagbukel, Narvacan, Quirino, Salcedo, San Emilio, San Esteban, San Ildefonso, San Juan, San Vicente, Santa, Santa Catalina, Santa Cruz, Santa Lucia, Santa Maria, Santiago, Santo Domingo, Sigay, Sinait, Sugpon, Suyo, Tagudin, and City of Vigan, Ilocos Sur; Bacnotan, Balaoan, Bauang, and Caba, La Union; Abulug, Allacapan, Amulung, Aparri, Baggao, Claveria, Lal-Lo, Lasam, Peñablanca, Tuao, and Tuguegarao City, Cagayan.

Intensity IV was also felt in Flora, Apayao; City of Baguio; Bokod, and Itogon, Benguet; City of San Fernando, and Sudipen, La Union; Enrile, Iguig, and Solana, Cagayan;

Intensity III in Laoac, City of Urdaneta, and Villasis, Pangasinan; City of Dagupan; Baler, Aurora; and

Intensity II in Labrador, Pangasinan; San Manuel, Isabela.

The following instrumental intensities were also logged by Phivolcs:

Intensity V: Gonzaga, Penablanca, Claveria, Cagayan; Pasuquin, Laoag City, Ilocos Norte; Vigan City, Ilocos Sur;

Intensity IV: Bangued, Abra;

Intensity III: Baler, Aurora; Ilagan, Isabela;

Intensity II: Bayombong, Nueva Vizcaya; Urdaneta, Dagupan City, Pangasinan; Madella, Quirino;

Intensity I: Dinalupihan, Bataan; Bulakan, Calumpit, Malolos City, Plaridel, Bulacan; Pasig City, Navotas City; Cabanatuan City and San Jose, Nueva Ecija; Guagua, Pampanga; Umingan, Sison, Bolinao, Infanta, and Bani, Pangasinan; Polillo, Mauban, and Infanta, Quezon; Tanay and Taytay, Rizal; Ramos, Tarlac; Iba, Zambales

Instrumental intensity is determined using an intensity meter that measures ground acceleration, whereas reported intensity is the traditional method for determining the magnitude of an earthquake based on reports from people who felt it.

According to Phivolcs, both aftershocks and damage are expected from the earthquake.

So far, the quake has generated 368 aftershocks as of 6 a.m. Wednesday. At least 46 of these were plotted or located, and four were felt.

The aftershocks ranged from magnitude 1.4 to 4.