Fault Distribution, Segmentation and Earthquake Generation Potential of the Philippine Fault in Eastern Mindanao, Philippines
Jeffrey S. Perez*, Hiroyuki Tsutsumi**, Mabelline T. Cahulogan*,
Desiderio P. Cabanlit*, Ma. Isabel T. Abigania*, and Takashi Nakata***
*Philippine Institute of Volcanology and Seismology – Department of Science and Technology (PHIVOLCS-DOST), PHIVOLCS Bldg., C.P. Garcia Avenue, U. P. Diliman Campus, Quezon City 1101, Philippines
**Department of Geophysics, Kyoto University, Kitashirakawa-oiwake-cho, Sakyo-ku, Kyoto 606-8502, Japan
***Department of Geography, Hiroshima University, Higashi-Hiroshima 739-8522, Japan
The 1,250-km-long, NNW-trending, arc-parallel Philippine fault, one of the world’s most active tectonic structures, traverses the Philippine archipelago and has been the source of surface-rupturing earthquakes during the last four centuries. In this paper, we will discuss Philippine fault distribution and segmentation in Mindanao Island by integrating detailed fault mapping together with new geological and paleoseismic data and the analysis of historical surface-rupturing earthquakes. Using geometric segmentation criteria, we have identified nine geometric segments separated by discontinuities such as en echelon steps, bends, changes in strike, gaps, steps and bifurcation in the surface trace. Fault segments ranges from 20 to 100 km in length and are capable of generating earthquakes of Mw6.6 to Mw7.4. The results of our study have important implications for earthquake generation potential and seismic hazard assessment of the Philippine fault in Mindanao Island.
-  C. R. Allen, “Circum-Pacific faulting in the Philippines-Taiwan region,” Journal of Geophysical Research, Vol.67, No.12, pp. 4795-4812, 1962.
-  M. A. Aurelio, “Shear partitioning in the Philippines: Constraints from Philippine fault from global positioning system data,” Island Arc, Vol.9, No.4, pp. 584-597, 2000.
-  E. Barrier, P. Huchon, and M. Aurelio, “Philippine fault: A key for Philippine kinematics,” Geology, Vol.19, No.1, pp. 32-35, 1999.
-  M. L. P. Bautista and K. Oike, “Estimation of the magnitudes and epicenters of Philippine historical earthquakes,” Tectonophysics, Vol.317, Nos.1-2, pp. 137-169, 2000.
-  H. Tsutsumi and J. S. Perez, “Large-scale active fault map of the Philippine fault based on aerial photograph interpretation,” Active Fault Research, No.39, pp. 29-37, 2013.
-  T. Nakata, A. Sangawa, and S. C. Hirano, “A report on tectonic landforms along the Philippine Fault Zone in Northern Luzon, Philippines,” Science Reports, Tohoku Univ., 7th Series (Geography), Sendai, Japan, Vol.27, No.2, pp. 69-93, 1977.
-  N. Pinet and J. F. Stephan, “The Philippine wrench fault system in the Ilocos Foothills, northwestern Luzon, Philippines,” Tectonophysics, Vol.183, pp. 207-224, 1990.
-  J. C. Ringenbach, N. Pinet, J. F. Stephan, and J. Delteil, “Structural variety and tectonic evolution of strike-slip basins related to the Philippine Fault System, northern Luzon, Philippines,” Tectonics, Vol.12, No.1, pp. 187-203, 1993.
-  M. A. Aurelio, E. Barrier, C. Rangin, and C. Muller, “The Philippine Fault in the late Cenozoic tectonic evolution of Bondoc-Masbate-N. Leyte area, central Philippines,” Journal of Southeast Asian Earth Science, Vol.6, No.3/4, pp. 221-238, 1991.
-  R. D. Quebral, M. Pubellier, and C. Rangin, “The onset of movement on the Philippine fault in eastern Mindanao: A transition from a collision to a strike-slip environment,” Tectonics, Vol.15, No.4, pp. 713-726, 1996.
-  J. S. Perez, H. Tsutsumi, and M. T. Cahulogan, “Tectonic geomorphology and paleoseismology of the Surigao segment of the Philippine fault, northeastern Mindanao Island, Philippines,” submitted to Journal of Asian Earth Sciences, 2014.
-  T. Nakata, H. Tsutsumi, R. S. Punongbayan, R. E. Rimando, J. A. Daligdig, A. S. Daag, and G. M. Besana, “Surface fault ruptures of the 1990 Luzon earthquake, Philippines,” Research Center for Regional Geography, Hiroshima University, Special Publication, No.25, p. 86, 1996.
-  E. M. Morante, “The Ragay Gulf earthquake of March 17, 1973, southern Luzon, Philippines,” Journal of the Geological Society of the Philippines, Vol.28, No. 2, pp. 1-31, 1974.
-  H. Tsutsumi, J. S. Perez, J. U. Marjes, K. L. Papiona, and N. T. Ramos, “Coseismic Displacement and Recurrence Interval of the 1973 Ragay Gulf Earthquake, Southern Luzon, Philippines,” Journal of Disaster Research, Vol.10, No.1, 2015 (this issue).
-  PHIVOLCS Quick Response Team, “The 15 February 2003 Masbate Earthquake,” PHILVOCS Special Report, No.5, p. 30, 2003.
-  G. Galgana, M. Hamburger, R. McCaffrey, E. Corpuz, and Q. Z. Chen, “Analysis of crustal deformation in Luzon, Philippines using geodetic observations and earthquake focal mechanisms,” Tectonophysics, Vol.432, Nos.1-4, pp. 63-87, 2007.
-  D. P. Schwartz and K. J. Coppersmith, “Fault behavior and chracteristic earthquakes: examples from the Wasatch and San Andreas fault zones,” Journal of Geophysical Research, Vol.89, pp. 5681-5698, 1984.
-  C. M. dePolo, D. G. Clark, D. B. Slemmons, and A. R. Ramelli, “Historical surface faulting in the Basin and Range province, western North America: implications for fault segmentation,” Journal of Structural Geology, Vol.13, No.2, pp. 123-136, 1991.
-  S. G.Wesnousky, “Predicting the endpoints of earthquake ruptures,” Nature, Vol.114, pp. 358-360, 2006.
-  P. Segall and P. D. Pollard, “Mechanics of discontinuous faults,” Journal of Geophysical Research, Vol.85, pp. 4337-4350, 1980.
-  P. G. Okubo and K. Aki, “Fractal geometry in the San Andreas fault system,” Journal of Geophysical Research, Vol.92, pp. 345-355, 1987.
-  R. H. Sibson, “Effects of fault heterogeneity on rupture propagation,” in “Directions in Paleoseismology,” A. J. Crone and E. M. Omdahl (Eds.), United States Geological Survey Open File Report, Nos.87-673, pp. 362-373, 1987.
-  P. L. K. Knuepfer, “Implications of the characteristics of end-points of historical surface fault ruptures for the nature of fault segmentation,” in “Fault Segmentation and Controls of Rupture Initiation and Termination,” D. P. Schwartz and R. H. Sibson (Eds.), United States Geological Survey Open File Report, Nos.89-315, pp. 193-228, 1989.
-  R. E. Wallace (Ed.), “The San Andreas fault system, California,” United States Geological Survey Professional Paper 1515, p. 283, 1990.
-  H. Tsutsumi and A. Okada, “Segmentation and Holocene surface faulting on the Median Tectonic Line, southwest Japan,” Journal of Geophysical Research, Vol.101, pp. 5855-5871, 1996.
-  A. M. C. Sengör, O. Tüysüz, C. İmren, et al., “The North Anatolian fault: a new look,” Annual Reviews Earth Planet Science, Vol.33, pp. 37-112, 2005.
-  K. Sieh and D. Natawidjaja, “Neotectonics of the Sumatran fault, Indonesia,” Journal of Geophysical Research, Vol.105, pp. 28295-28326, 2000.
-  M. Pubellier, R. Quebral, C. Rangin, B. Deffontaines, C. Muller, J. Butterlin, and J. Manzano, “The Mindanao collision zone: A soft collision event within a continuous Neogene strike-slip setting,” Journal of Southeast Asian Earth Sciences, Vol.6, No.3/4, pp. 239-248, 1991.
-  G. F. Moore and E. A. Silver, “Collision processes in the northen Molucca Sea,” in D. E. Hayes (Ed.), “The tectonic and geologic evolution of Southeast Asian seas and islands: Part 2,” American Geophysical Union Monograph, Vol.27, pp. 360-372, 1983.
-  R. E. Bischke, J. Suppe, and R. Delpilar, “A new branch of the Philippine Fault System as observed from aeromagnetic and seismic data,” Tectonophysics, Vol.183, Nos.1-4, pp. 243-264, 1990.
-  Philippine Institute of Volcanology and Seismology (PHIVOLCS), “Earthquake Catalogue from 2007-2012,” 2012.
-  W. C. Repetti, “Catalogue of Philippine earthquakes, 1589-1899,” Bulletin of the Seismological Society of America, Vol.36, No.3, pp. 133-322, 1946.
-  J. S. Perez, H. Tsutsumi, M. T. Cahulogan, D. P. Cabanlit, and C. D. Pogay, “Paleoseismology along the southern segments of the Philippine fault, eastern Mindanao, Philippines,” 2014 (in preparation).
-  J. S. Perez and H. Tsutsumi, “Paleoseismic studies along the Philippine fault zone, eastern Mindanao, Philippines,” Proceeding of the 2011 Japan Geoscience Union Meeting, 2011.
-  D. L. Wells and K. J. Coppersmith, “New Empirical Relationships Among Magnitude, Rupture Length, Rupture Width, Rupture Area, and Surface Displacement,” Bulletin of the Seismological Society of America, Vol.84, No.4, pp. 974-1002, 1994.