碩士 / 國立中正大學 / 地震研究所 / 105 / In this research, we calculated the vertical seismic waveform data from the IRIS seismic data center which the period is from 2000 to 2012 to analyze the surface wave dispersion curve and construct the 3D Rayleigh-wave group velocity and azimuthal anisotropy structure beneath the South China Sea (SCS).
The research region is among 10°S-30°N and 10°-130°E, 18 broadband stations were chose in this area that the ray density could cover the SCS. Hence, we adopted the Multiple Filter Technique (MFT) which proposed by Dziewonski et al. (1969) to analyze Rayleigh-wave dispersion curves at periods from 20s to 100s. In this study, we obtained 3288 dispersion curves from the teleseismic data. Finally, we used the inversion method which proposed by Debayle, E. and M. Sambridge (2004) to obtain the tomography and azimuthal anisotropy map.
From the results of short periods, the tomography model exhibited high velocity region which reflects the thickness of the basin and low velocity region that refers to the volcanic island arc around the SCS. By the way, azimuthal anisotropy shows the orientation of crack within the crust. For the long period, the high velocity region reflects the rock characteristic in the bottom of basin and the azimuthal anisotropy exhibits the upper mantle flow direction and the expansion center as well. In addition, the results of vertical profiles also reveal a phenomena that the oceanic crust covered to continental crust beneath the Southwestern basin and Central basin in the SCS. According to the above results, we can learn more about the evolution of the SCS.
| Identifer | oai:union.ndltd.org:TW/105CCU00140009 |
| Date | January 2017 |
| Creators | CHENG, CHIA-HSUAN, 鄭佳烜 |
| Contributors | CHEN, CHAU-HUEI, 陳朝輝 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 70 |
Page generated in 0.0118 seconds