Philippine Mobile Belt

Within the Belt, a number of crustal blocks or microplates which have been shorn off the adjoining major plates are undergoing massive deformation.

[5] Palawan with the Calamian Islands and the Sulu Archipelago with the Zamboanga Peninsula of western Mindanao are the tops of two protruding north-eastern arms of the Sunda plate.

Subduction of Late Oligocene to Early Miocene South China sea oceanic crust occurs at the Manila Trench.

Any suggestion that Northern Luzon is not part of the Philippine Mobile Belt is not borne out by the detailed fault mapping of Pinet and Stephan (1989),[16] and others.

The composition of the Philippine Mobile Belt is generally interpreted as a collage of a large variety of blocks or terrane of diverse origin amalgamated before collision with the Eurasian margin.

[19] In Luzon, the Middle Oligocene to Late Miocene age of the arc is well constrained stratigraphically as well as radiometrically.

Sajona and others (1993) analyzed Pliocene-Pleistocene adakitic rocks in Zamboanga Peninsula and mention a possible association with activity along the Philippine Fault in Surigao and northern Davao.

The distribution of Philippine Pliocene-Quaternary volcanoes generally reflects the activity along subduction zones presently bounding the archipelago.