The major fault lines are those trenches running along the eastern region of the Philippines (Surigao, Samar, Bicol, Quezon, Isabela).
In Kalinga Province, two major fault lines pass through a northeasterly direction from Mountain Province to Tinglayan -- Mountain Mosimos-Lubuagan-Pasil-Balbalan. Another one passes through the same route from the corner boundary of Mountain Province and Abra to Tinglayan-Lubuagan and ends at Gobgob, Tabuk.
Marikina City is also lying on a major fault line. Another major fault lines traverse the municipalities of Sogod, Libagon, St. Bernard and San Juan to Panaon Island in Leyte.Source: