After magnitude-6.9 quake, aftershocks shake Mindanao

(Update - 8:10 pm) At least four more aftershocks, one of them measuring a powerful magnitude-7.1, rocked parts of Mindanao Saturday morning after a magnitude-6.9 quake rocked the same area early Saturday morning, the Philippine Institute of Volcanology and Seismology said. The Philippine Institute of Volcanology and Seismology said the first quake was recorded at 6:08 a.m. at magnitude 6.9, and was tectonic in origin. Its epicenter was traced to 94 km southwest of Cotabato City, and was felt at Intensity II in Surigao City and General Santos City. Phivolcs also said the first aftershock was recorded at 6:51 a.m., and measured at magnitude 6.7. Its epicenter was traced to 97 km southwest of Cotabato City, and was felt at Intensity II in Butuan City and Surigao City. A second aftershock was recorded at 7:15 a.m., and the epicenter was traced to 98 km southwest of Cotabato City. It was tectonic in origin and measured at magnitude 7.1. The magnitude-7.1 quake was felt at Intensity IV in Tanjay City and San Jose City, Negros Oriental; Intensity III in General Santos City; Lingig, Surigao del Sur; San Jose and Hamtic, Antique; Irosin in Sorsogon and Sorsogon City; Intensity II in Cotabato City; Kidapawan City; Dipolog City; Tacloban City; Davao City; Legazpi City; Cagayan de Oro City; Cebu City; Dumaguete City. The quake was felt at Intensity II as far as Manila and Antipolo Cities. Phivolcs said a possible source of Saturday morning's tectonic quakes was the deformation of the subducted slab of the Molucca Sea Plate. NDCC: No reported damage due to quakes Despite the powerful earthquake and aftershocks, the National Disaster Coordinating Council (NDCC) said it has not yet monitored any damage in affected areas as of Saturday afternoon. “There is no damage. Although it’s 6.1 intensity, there are no reported damage in the Cotabato City areas," NDCC executive officer and concurrent Office of Civil Defense administrator Benito Ramos told reporters on Saturday. He added that even minor damage were not seen in buildings near the epicenter, although NDCC personnel are still monitoring areas affected by the earthquake. “We have people there. It’s just a little shake and it did not cause damage. We did not even see cracks (on structures)," he said. Philvolcs officials earlier said that damage due to the tectonic earthquake was unlikely, and likewise allayed fears of a tsunami resulting from the tremors. USGS records more aftershocks The United States Geological Survey measured the second aftershock at magnitude 7.4. The USGS also said a third aftershock was recorded at 9:44 a.m., at magnitude 5.3. It said the epicenter was at 90 km southwest of Cotabato, 135 km south-southeast of Pagadian, 170 km west-northwest of General Santos City, or 930 km south-southeast of Manila. USGS recorded a fourth aftershock at 1:35 p.m., measuring it at magnitude 6.2. It said the epicenter was at 135 km south-southwest Cotabato; 175 km west of General Santos City; 180 km south of Pagadian; or 975 km south-southeast of Manila.—LBG/JV, GMANews.TV