PHIVOLCS EARTHQUAKE UPDATE

Republic of the Philippines
Department of Science and Technology

PHILIPPINE INSTITUTE OF VOLCANOLOGY AND SEISMOLOGY
PHIVOLCS Bldg., C.P. Garcia Ave., University of the Philippines Campus, Diliman, Quezon City
Tels. 426-1468 to 79; Fax: 929-8366 (director’s office); 927-1087 (seismology); 926-3225

PHIVOLCS EARTHQUAKE UPDATE

11:00 AM, 21 October 2006


A magnitude 5.2 earthquake occurred at 10:30 PM on October 20, 2006 and was felt in Southern Luzon. The epicenter was located offshore between the islands of Mindoro and Marinduque at 13.43°N, 121.53°E, or about 35 km West of Boac, Marinduque. It was reportedly felt at (PEIS) Intensity V in Marinduque, Naujan (Mindoro Oriental), Batangas City and Bauan (Batangas); at Intensity IV in Manila City, Lipa City (Batangas) and San Pablo City (Laguna) ; at Intensity III in Makati City and Puerto Galera (Oriental Mindoro), Talisay (Batangas), Lucban (Quezon); at Intensity II in Quezon City, Tagaytay City and Guinayangan (Quezon). The possible source of this earthquake is movement along the eastern segment of Lubang Fault.

Three (3) aftershocks were felt as of 11 AM October 21, 2006 - at 01:27 AM (magnitude 3.7), at 06:09 AM (magnitude 4.7) and 10:53 AM. The 01:27 AM event was felt at intensity III in Lipa City and San Pablo City; at Intensity II in the areas of Taal, Buco, Talisay (Batangas), Quezon City, Muntinlupa, Carmona (Cavite), Tagaytay City and Lucban (Quezon). The 06:09AM event was reportedly felt at Intensity III in Batangas City, Cabuyao (Laguna), Manila; and at Intensity II in Quezon City, Manila City and Lucban (Quezon). The 10:53 AM event was felt at Intensity III at San Pablo City, Intensity II at Tanauan (Batangas) and Intensity I at Talisay (Batangas). These aftershocks were located near the epicenter of the October 20 10:30 PM earthquake.

No report of damages have been received as of this update. Although the epicenter of the earthquake is located offshore, PHIVOLCS has not issued a tsunami watch in the coastal areas of Southern Luzon as these earthquakes have magnitudes that are not capable of generating destructive tsunamis. However, PHIVOLCS still expects aftershocks to continue occurring in the next few days which may be felt especially within the vicinity of the epicenter. Aftershocks are normally of lower magnitude than the mainshock but may vary in felt intensities as the epicenters of these aftershocks become close to populated areas. Because of this, PHIVOLCS is continuously monitoring the area and any new development will be relayed to all concerned.




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