This project aims to refine the mapping and characterization of active and potentially active structures in Central Philippines by combining remote sensing and geophysical datasets to detect and interpret lineaments that may correspond to faults. The work targets known systems such as the Verde Passage Fault and Sibuyan Sea Fault, while also searching for previously unmapped lineaments that could be structurally significant but obscured by dense vegetation, rugged terrain, or limited access. Because many Philippine fault traces remain incompletely constrained (especially offshore or in poorly mapped corridors), the study focuses on extracting fault-related surface expressions and linking them to deeper crustal boundaries, with the practical goal of strengthening the basis for geohazard monitoring and risk assessment across both land and surrounding seas.
The project uses an integrated workflow that merges gravity anomaly interpretation with satellite-based lineament mapping. Subsurface-related lineaments will be identified using global gravity datasets (WGM2012, 2′×2′ resolution) processed through regional–residual separation and derivative filtering (e.g., edge detection) to enhance structural breaks that may reflect lithologic boundaries and crustal discontinuities. These gravity-derived lineaments will be complemented by surface lineaments mapped from interferometric SAR (IFSAR) topography/DEM and optical imagery (Landsat-9, 30 m), where geomorphic indicators (linear valleys, aligned scarps, drainage deflections, ridge-line offsets) are digitized and analyzed in a GIS environment. The lineament sets from remote sensing and gravity will then be cross-checked against existing catalogs and references (e.g., PHIVOLCS and other published/archival sources) to evaluate consistency with recognized tectonic trends, assess which surface features plausibly connect to deeper structures, and produce integrated maps that highlight fault-related features across onshore and offshore domains.
The main output is a set of geophysical and remote-sensing-derived lineament products that improve how active structures are visualized and interpreted in Central Philippines, including areas where field mapping is difficult or where faults extend offshore. By integrating gravity signatures (as a proxy for subsurface structure) with topographic and imagery-based lineaments (as surface expressions), the study strengthens confidence in distinguishing “just another line on a map” from features that are genuinely fault-related. In hazard terms, better-constrained structural interpretations support more informed earthquake-source assessment, guide priorities for targeted ground validation and monitoring, and help reduce uncertainty in regions where faults are currently inferred only as approximate traces. In short: fewer blind spots in the fault map, which is the kind of improvement people only appreciate after the ground starts moving.
This research addresses the UN Sustainable Development Goals for Sustainable Cities and Communities (SDG 11) and Industry, Innovation, and Infrastructure (SDG 9).
Cover photo from Armada, L,. Hsu, S. K., Ku, .C Y., Doo, W. B,. Wu, W. N,. Dimalanta, C. B., &Yumul, G. P. (2012). Possible northward extension of the Philippine Fault Zone offshore Luzon Island (Philippines). Marine Geophysical Research, 3, 369-377. https://doi.org/10.1007/s11001-013-9169-5
