Rd. Quebral et al., THE ONSET OF MOVEMENT ON THE PHILIPPINE FAULT IN EASTERN MINDANAO - ATRANSITION FROM A COLLISION TO A STRIKE-SLIP ENVIRONMENT, Tectonics, 15(4), 1996, pp. 713-726
The spatial and temporal evolution of eastern Mindanao from a zone of
active are-are collision to one of pure strike slip environment is add
ressed. This is made possible by tracing the Philippine Fault, confine
d to a well defined and narrow zone of deformation, and by differentia
ting from it earlier collision-related compressional features, whose d
eformation is distributed over a broad zone. A diachronous unconformit
y marking the end of collision-related deformation reflects the southw
ard propagating nature of the collision and provides limits on the age
of initiation of the Philippine Fault. This diachronism suggests that
the initiation of the Philippine Fault is related to the completion o
f the collision. We show the rapidity at which formation and propagati
on of the fault follows the locking of the collision zone. We likewise
demonstrate that the Philippine Fault reactivates pre-existing collis
ional features in cutting across the southern Pacific Cordillera.