The Crustal Structures beneath the Song Ma Fault Zone Inferred from Inversion of Teleseismic Receiver Functions

• Main Authors: Su, Cheng Ming, 蘇建旻
• Other Authors: Chen, Chau Huei
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/58983218774048225471

碩士 === 國立中正大學 === 地震研究所 === 102 === This pilot study analyzes earthquake data recorded by the broadband seismic network deployed along the Song Ma fault, northern Vietnam. We have selected teleseismic events with Mw≥5, and epicenter distance is between 30o and 90o. A Multiple-Taper Correlation (MTC) method is adapted to calculate receiver functions (RFs) for each station. The converted phase, such as P-to-S obtained from RFs, allows us have insights on the characteristics of crustal structures including the dip of discontinuous interface and anisotropy as well. The above properties have great effects on amplitudes and arrival time of RFs. Thus, we have applied an initial anisotropic velocity model to obtain synthetic RFs. Furthermore, we used a Neighborhood Algorithm to search an optimum model which had minimum misfit between the observed RFs and synthetic ones. Our preliminary results indicate that the depth of the Moho discontinuity in the Song Ma fault zone is between 25 km and 35 km, and the S-wave velocity is from 3.6 km/s to 4.5 km/s.