HR: 1340h
AN: T43A-1372    [Abstracts]
TI: DInSAR Observation of a Graben-Like Structure in Southwestern Taiwan and its Tectonic Implication
AU: * Yen, J
EM: yen@gly.fsu.edu
AF: Center for Space and Remote Sensing Research, National Central University, No.300, Jhongda Rd., Jhongli City, Tao 320 Taiwan
AU: Chang, C
EM: cpchang@csrsr.ncu.edu.tw
AF: Center for Space and Remote Sensing Research, National Central University, No.300, Jhongda Rd., Jhongli City, Tao 320 Taiwan
AU: Chen, K
EM: dkschen@csrsr.ncu.edu.tw
AF: Center for Space and Remote Sensing Research, National Central University, No.300, Jhongda Rd., Jhongli City, Tao 320 Taiwan
AB: Taiwan is located on the southeastern periphery of the Eurasian plate and in the westernmost corner of the Philippine Sea plate, and is part of two subduction systems, the Ryukyu subduction system to the northeast and the Manila subduction system to the south-southwest. The Philippine Sea plate is moving toward the Eurasian plate at about 8.2 cm/yr along 307° azimuth. This continuous plate motion has provided the source of energy to produce the mountainous island. Because of the continuous convergence between the two plates, the island of Taiwan experienced a significant amount of crustal shortening and was thought to be a compressional regime in most of the island except for the northeastern end of Taiwan and some part of the Central Ranges (which can be attributed to the opening of Okinawa trough and gravitational collapse, respectively.) However, recent results from differential interferometry suggested that a east-west trending, graben-like deformation zone existed in the southwestern Taiwan. Differential interferometry was used in our study to generate six interferograms of southwestern Taiwan area from radar images acquired by ERS-2 satellite launched by European Space Agency. We monitored the surface deformation pattern from 1997 to 2002. The result of this research indicated that throughout 1997 to 2002, a deformation zone stretched from Minsyong to Peikang that is roughly 10km in the east-west direction and 5km in the north-south, consistently exhibited deformation. The deformation appeared to be a fold rather than a fault on the surface. From the published subsurface structure, it is possible that this area exhibited a deep-seated normal fault that was covered by sedimentary sequences above. Further investigation using other geodetic and geophysical tools are needed to provide more information about this deformation zone and to illustrate its tectonic meaning.
DE: 1209 Tectonic deformation (6924)
DE: 1240 Satellite geodesy: results (6929, 7215, 7230, 7240)
DE: 8002 Continental neotectonics (8107)
DE: 8155 Plate motions: general (3040)
DE: 8170 Subduction zone processes (1031, 3060, 3613, 8413)
SC: Tectonophysics [T]
MN: Fall Meeting 2005