Evaluation of earthquake potential and surface deformation by Differential Interferometry

Abstract Uncertainties in the length of active faults and the styles of deformation often hamper the evaluation of seismic potentials in a region. In the area near Chiayi City of southwestern Taiwan, where historically there have been many strong earthquakes, complex fault and fold systems produced by regional tectonic forces and the subsequent deformation are frequently obscured by vegetation and anthropogenic effects; and therefore detailed deformation information has not been available for evaluation of the seismic potential. By stacking the results from Differential Interferometry and removing the ambiguity of interferograms using GPS data, we were able to retrieve surface deformation information about the area under consideration near Chiayi City. In our results, we found that the Meishan fault to the north of Chiayi City extended 10 km to the west of its currently documented area and served as a geological boundary separating the northern part, where sediments were thicker, from the southern part of the westward extension of the Meishan fault. Chiayi City was under active deformation by a double plunging fold with vertical uplift rate at approximately 1 cm/yr. Frequent seismicity and active deformation allowed the tectonic stress to permute between strike–slip and thrust in this area. Continuous folding of Chiayi City and episodic large earthquakes along the Meishan Fault posed a serious threat of seismic hazards in this region, and called for continuous monitoring of the area.

[1]  C. Wang,et al.  Illustrating 100 years of Taiwan seismicity , 1998 .

[2]  Wei-Hau Wang,et al.  Static Stress Transferred by the 1999 Chi-Chi, Taiwan, Earthquake: Effects on the Stability of the Surrounding Fault Systems and Aftershock Triggering with a 3D Fault-Slip Model , 2004 .

[3]  Shui-Beih Yu,et al.  Velocity field of GPS stations in the Taiwan area , 1997 .

[4]  Y. Tsai,et al.  Slab breakoff as a mechanism for flipping of subduction polarity in Taiwan , 2000 .

[5]  C. W. Chen,et al.  Two-dimensional phase unwrapping with use of statistical models for cost functions in nonlinear optimization. , 2001, Journal of the Optical Society of America. A, Optics, image science, and vision.

[6]  J. Angelier,et al.  Active deformation of Taiwan from GPS measurements and numerical simulations , 2001 .

[7]  Howard A. Zebker,et al.  Phase unwrapping for large SAR interferograms: statistical segmentation and generalized network models , 2002, IEEE Trans. Geosci. Remote. Sens..

[8]  C. Werner,et al.  Radar interferogram filtering for geophysical applications , 1998 .

[9]  F. Webb,et al.  Surface deformation and coherence measurements of Kilauea Volcano, Hawaii, from SIR C radar interferometry , 1996 .

[10]  F. Omori,et al.  Preliminary Note on the Formosa Earthquake of March 17, 1906 , 1907 .

[11]  P. Rosen,et al.  SYNTHETIC APERTURE RADAR INTERFEROMETRY TO MEASURE EARTH'S SURFACE TOPOGRAPHY AND ITS DEFORMATION , 2000 .

[12]  Thomas J. Flynn,et al.  TWO-DIMENSIONAL PHASE UNWRAPPING WITH MINIMUM WEIGHTED DISCONTINUITY , 1997 .

[13]  K. Feigl,et al.  Radar interferometry and its application to changes in the Earth's surface , 1998 .

[14]  R. Pratt,et al.  Deep Eustatic Terrace Levels: Further Speculations , 1974 .

[15]  J. Angelier,et al.  Three-dimensional modeling of the behavior of the oblique convergent boundary of southeast Taiwan: friction and strain partitioning , 2001 .

[16]  S. Critelli,et al.  Provenance of the Lower Tertiary Murree redbeds (Hazara-Kashmir Syntaxis, Pakistan) and initial rising of the Himalayas , 1994 .

[17]  David Jon Furbish,et al.  Fluid Physics in Geology: An Introduction to Fluid Motions on Earth's Surface and within Its Crust , 1996 .

[18]  Louis S. Teng.  Geotectonic evolution of late Cenozoic arc-continent collision in Taiwan , 1990 .

[19]  Louis S. Teng.  Extensional collapse of the northern Taiwan mountain belt , 1996 .

[20]  D. Schmidt.  Time-dependent land uplift and subsidence in the Santa Clara Valley , 2003 .

[21]  P. Tapponnier,et al.  Cretaceous paleomagnetic results from western Tibet and tectonic implications , 1993 .

[22]  W. Brown.  Synthetic Aperture Radar , 1967, IEEE Transactions on Aerospace and Electronic Systems.

[23]  Bénédicte Fruneau,et al.  Uplift of Tainan Tableland (SW Taiwan) revealed by SAR Interferometry , 2001 .

[24]  P. Rosen,et al.  On the derivation of coseismic displacement fields using differential radar interferometry: The Landers earthquake , 1994, Proceedings of IGARSS '94 - 1994 IEEE International Geoscience and Remote Sensing Symposium.

[25]  J. Suppe.  Mechanics of mountain-building and metamorphism in Taiwan , 1981 .

[26]  Robert J. Mellors,et al.  Comparison of Four Moderate-Size Earthquakes in Southern California Using Seismology and InSAR , 2004 .

[27]  Y. Bock,et al.  Strain partitioning during oblique plate convergence in northern Sumatra: Geodetic and seismologic constraints and numerical modeling , 2000 .

[28]  Katsuaki Koike,et al.  Detection of topographic changes associated with volcanic activities of Mt. Hossho using D-InSAR , 2004 .

[29]  Robert K. Mark,et al.  Statistical relations among earthquake magnitude, surface rupture length, and surface fault displacement , 1984 .

[30]  Bellier,et al.  Slip‐partitioning and fore‐arc deformation at the Sunda Trench, Indonesia , 1998 .

[31]  Eric J. Fielding,et al.  Aseismic deformation of a fold-and-thrust belt imaged by synthetic aperture radar interferometry near Shahdad, southeast Iran , 2004 .

[32]  J. Suppe.  Kinematics of arc-continent collision, flipping of subduction, and back-arc spreading near Taiwan , 1984 .

[33]  C. W. Chen,et al.  Network approaches to two-dimensional phase unwrapping: intractability and two new algorithms. , 2000, Journal of the Optical Society of America. A, Optics, image science, and vision.

[34]  S. Stein,et al.  A model for the motion of the Philippine Sea Plate consistent with NUVEL‐1 and geological data , 1993 .

[35]  R. Hall.  Cenozoic geological and plate tectonic evolution of SE Asia and the SW Pacific: computer-based reconstructions, model and animations , 2002 .

[36]  C. S. Ho.  A synthesis of the geologic evolution of Taiwan , 1986 .

[37]  S. Acharyya.  Break-up of the Greater Indo-Australian Continent and accretion of blocks framing South and East Asia , 1998 .

[38]  R. Dorsey.  Provenance Evolution and Unroofing History of a Modern Arc-Continent Collision: Evidence from Petrography of Plio-pleistocene Sandstones, Eastern Taiwan , 1988 .

[39]  Char‐Shine Liu,et al.  Strike-slip faults offshore southern Taiwan: implications for the oblique arc-continent collision processes , 1997 .

[40]  T. Lee,et al.  Cenozoic plate reconstruction of Southeast Asia , 1995 .

[41]  H. Kao,et al.  Active detachment of Taiwan illuminated by small earthquakes and its control of first-order topography , 2002 .

[42]  L. Jolivet,et al.  Kinematics, topography, shortening, and extrusion in the India‐Eurasia collision , 1992 .