臺灣博碩士論文加值系統

在近代對於地殼構造、厚度以及莫荷面深度的研究，有不少是利用接收函數(Receiver functions, RFs)的方法去獲得。東亞地區是印度板塊、歐亞板塊、菲律賓海板塊以及太平洋板塊之間互相作用之區域，因此造成東亞地區複雜的地體構造與地表變形。印度板塊和歐亞大陸板塊約在第三紀(Tertiary)左右開始碰撞，使西藏高原因為岩石圈增厚而抬升，並推動中南半島。是故，在北越Song Ma斷層剪切帶其區域應力特性及地體構造與上述此區域的板塊擠壓碰撞有密切關係。在目前的文獻中大多數探討區域多是集中於北越紅河斷層帶(Red river fault zone)之鄰近區域與Song Ma斷層帶西北段，而對於Song Ma斷層帶東南段這部分之地下構造上仍處於不明瞭的情況。為了突破此情況，國立中正大學於2009年與越南地質科學院合作在北越Song Ma斷層剪切帶東南段設置了12部臨時的寬頻地震儀器，由於在此區域目前所監測的地震大多發生於地殼淺部，地殼深部的構造則受限於地震數量稀少使得對於深層的地下構造不甚了解。為了解決這個問題，本研究利用遠震接收函數來解析深層的地下構造、莫荷面深度以及各層非均向性之特性與方向。初步結果顯示了此區之莫荷面深度介於26~35公里深之間，S波速度值介於4.1~4.7( km/sec)。在非均向性結果的部分大致可分類成兩類，一類是在0~20公里深的地殼中非均向性慢軸的部分，慢軸方向結果顯示大致垂直斷層構造；另一類是深於20公里下部地殼及上部地函中非均向性快軸的部分，其快軸方向結果顯示大致平行於在270至240個百萬年前印度支那地塊(Indochina block)向北移動與南中國地塊(South china block)發生碰撞的方向。由以上結果可讓我們更進一步瞭解Song Ma斷層帶東南段及其鄰近區域的地體演化。

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.

致謝 ii
中文摘要 iii
Abstract iv
目錄 5
圖目錄 6
表目錄 8
第一章 緒論 9
1.1 研究動機與目的 9
1.2 研究區域概況 10
1.3 前人研究 11
第二章 研究方法與原理 16
2.1. 正演方法 16
2.1.1. 接收函數(Receiver Functions)原理 16
2.1.2. 正演模型(Forward modeling) 18
2.2. 反演方法 21
2.2.1. 鄰域演算法(Neighborhood Algorithm) 21
2.2.2. 誤差函數(Misfit Function) 22
2.3. 剪波分裂(Shear wave splitting) 23
2.3.1. 快剪波極化角度(Polarization angle, ψ) 24
2.3.2. 快剪波與慢剪波的延遲時間(Delay time, δt) 24
2.3.3. 波形計算與相關係數、信賴區間計算 25
第三章 資料處理與分析 35
3.1 資料選取與處理流程 35
3.2 參數設定與模型假設 36
3.2.1 接收函數(Receiver Functions) 36
3.2.2 剪波分裂(Shear wave splitting) 38
3.3 資料分析與結果 38
第四章 結果與討論 53
4.1. 速度構造 53
4.2. 非均向性 54
第五章 結論 64
References 66
附錄A 70
附錄B 71
附錄C 73

Bai, L., Tian, X., Ritsema, J., 2010. Crustal structure beneath the Indochina Peninsula from teleseismic receiver functions. Geophysical Research Letters 37, L24308. doi:10.1029/2010GL044874.

Bianchi, I., Piana Agostinetti, N., De Gori, P. & Chiarabba, C., 2008. Deep structure of the Colli Albani volcanic district (central Italy) from receiver function analysis, J. geophys. Res., 113, B09313, doi:10.1029/2007JB005548.

Brocher, T. M. and Christensen, N. I., 1990. Seismic anisotropy due to
preferred mineral orientation observed in shallow crustal rocks in
southern Alaska, Geology,18,737-740.

Burdick, L. J., and C. A. Langston, 1977. Modeling crustal structure through the use of converted phases in teleseismic body-wave forms, Bull. Seism. Soc. Am., 67, 677-691.

Cassidy, J. F., 1992. Numerical experiments in broadband receiver function analysis, Bull. Seism. Soc. Am., 82, 1453-1474.

Crampin, S., 1984. Effective Elastic Constants for Wave Propagation through Cracked Solids, Geophys.J. Roy. Astron. Soc. 76, 135–145.

Crampin, S. and Zatsepin, S. V., 1995. Production seismology: the use of shear waves to monitor and model production in a poro-reactive and interactive reservoir. Proceeding of the 65th Annual International SEG Meeting, Houson, Expanded Abstracts, 199-202.

Davis, P., England, P. and Houseman, G., 1996, Comparison of shear wave splitting and finite strain from the India-Asia collision zone, J. Geophys. Res., 102, 27,511-27,522.

Farra, V., and L. Vinnik, 2000. Upper mantle stratification by P and S receiver functions, Geophys. J. Int., 141(3), 699– 712.

Faure, M., Lepvrier, C., Vuong, N. V., Tich V. V., Lin, W., Chen, Z., 2013. The South China Block-Indochina collision: where, when, and how? , Journal of Asian Earth Sciences, doi:10.1016/j.jseaes.2013.09.022

Findlay, R. H. and Trinh, P. T. , 1997. The structural setting od the Song Ma Anticlinorium, Vietnam and the Indochina-South China plate boundary problem, Gondwana Rsearch 1,11-33.

Flesch, L.M., Holt, W.E., Silver, P.G., Stephenson, M., Wang, C.Y., Chan, W.W., 2005. Constraining the extent of crust-mantle coupling in central Asia using GPS, geologic and shear wave splitting data. Earth Planet. Sci. Lett. 238, 248–268.

Frederiksen, A.W., and Bostock, M. G., 2000. Modeling teleseismic waves in dipping anisotropic structures, Geophys. J. Int., 141, 401– 412.

Frederiksen, A. W., Folsom, H. and Zandt, G., 2003. Neighbourhood inversion of teleseismic Ps conversions for anisotropy and layer dip, Geophys. J. Int., 155, 200–212, doi:10.1046/j.1365-246X.2003.02043.x.

Frederiksen, A. W., Folsom, H. and Zandt, G., 2004. Crustal fabric in the Tibetan Plateau based on waveform inversions for seismic anisotropy parameters, J. Geophys. Res., 109, B02312, 10.1029/2002JB002345.

Fouch, M., and Rondenay, S., 2006. Seismic anisotropy beneath stable continental interiors, Phys. Earth Planet. Inter., 158, 292-320.

Huang, Z., Wang, L., Xu, M., Liu, J., Mi, N., Liu, S., 2007. Shear wave splitting across the Ailao Shan-red River fault zone, SW China. Geophys. Res. Lett. 34, doi:10.1029/2007GL031236.

Kern, H., 1990. Laboratory seismic measurement: An aid in the interpretation of seismic field data, Terra Nova, 2, 617-628.

Kreyszig, E., 1970. Introductory mathematical statistics: principles and methods.

Lees, J., & Park, J., 1995. Multiple-taper spectral analysis: A stand-alone C-subroutine, Computers & Geosciences, 21, 199–236.

Levin, V. and Park, J., 1998. P-SH Conversions in layered media with hexagonally symmetric anisotropy: A CookBook, Pure appl. geophys. 151669–6970033–4553:98:040669–29.

Lev, E., Long, M.D., van der Hilst, R.D., 2006. Seismic anisotropy in Eastern Tibet from shear wave splitting reveals changes in lithospheric deformation. Earth. Planet. Sci. Lett. 251, 293–304.

Luo, Y., Huang, Z.X., Peng, Y.J., Zheng, Y.J., 2004. A study on SKS wave splitting beneath the China mainland and adjacent regions. Chinese J. Geophys. 47, 916–926.

Nguyen, V. D., Huang, B. S., Le, T. S., Dinh, V. T., Zhu, L. and Wen, K. L., 2013. Constraints on the crustal structure of northern Vietnam based on analysis of teleseismic converted waves. Tectonophysics, 601, 87-97.

Owens, T. J., G. Zant, and S.R. Taylor, 1984. Seismic evidence for an ancient rift beneath the Crumberland Plateau, Tennessee: A Detailed analysis of broadband teleseismic P waveforms, J. Geophys. Res., 89, 7783-7795.

Park, J., and Levin, V., 2000. Receiver functions from multiple‐taper spectral correlation estimates, Bull. Seismol. Soc. Am., 90, 1507–1520.

Phinney, R. A., 1964. Structure of the Earth’s crust from spectral behavior of long-period body waves, J. Geophys. Res., 69, 2997-3017.

Roselli, P., Piana, Piana Agostinetti, N. and Braun, 2010. Shear-velocity and anisotropy structure of a retreating extentional forearc (Tuscany, Italy) from receiver functionsinversion, Geophys. J. Int., 181, doi:10.1111/j.1365-264.

Sambridge, M., 1999a. Geophysical inversion with a neighbourhood algorithm— I. Searching a parameter space, Geophys. J. Int., 138, 479– 494.

Sambridge, M., 1999b. Geophysical inversion with a neighbourhood algorithm— II. Appraising the ensemble, Geophys. J. Int., 138, 727– 746. Sartori, R. (1990), The main results of ODP Leg 107 in the frame of Neogene to Recent geology of erityrrhenian areas, Proc. Ocean Drill. Program Sci. Results, 107, 715–730.

Sambridge, M., 2001. Finding acceptable models in nonlinear inverse problems using a neigbourhood algorithm, Inverse Problem, 17, 387-403.

Savage, M. K., 1999. Seismic anisotropy and mantle deformation: What have we learned from shear wave splitting?, Rev. Geophys., 37, 65-106.

Silver, P. G., 1996. Seismic anisotropy beneath the continents: Probing the depths of geology, Annu, Rev. Earth Planet. Sci., 24, 385-432.

Sol, S., Meltzer, A., Burgmann, R., van der Hilst, R.D., King, R., Chen, Z., Koons, P.O., Lev, E., Liu, Y.P., Zeitler, P.K., Zhang, X., Zhang, J., Zurek, B., 2007. Geodynamics of the southeastern Tibetan Plateau fromseismic anisotropy and geodesy. Geology 35, 563–566.

Tapponnier, P., Peltzer, G., Le Dain, A.Y., Armijo, R., Cobbold, P., 1982. Propagating extrusion tectonics in Asia: new insights from simple experiments with plasticine. Geology 10, 611–616.

Tapponnier, P., Lacassin, R., Leloup, P. H., Scharer, U., Dalai, Z., Haiwei, W., Xiaohan, L., Shaocheng, J., Lianshang, Z. and Jiayou, Z., 1990. The Ailao Shan/Red River metamorphic belt; Tertiary left lateral shear between Indochina and South China. Nature 343, 431–437.

Thomson, D. J., 1982. Spectrum estimation and harmonic analysis, IEEE Proc., 70, 1055–1096.

Wen, S., L. H. Phong, T. A. Vu, D. V. Toan, W. Y. Chang, C. H. Chen, (2011) The Seismicity and Focal mechanisms Analysis of the Ma-River Fault Area, Vietnam. International Worshop on Advanced Research in Geosciences in Asia --35th Anniversary of the Institute of Geological Sciences.

Zhang, S. and Karato, S. I., 1995, Lattice preferred orientation of olivine aggregates deformed in sample shear, Nature, 375, 774-777.

Zhao, L., Zheng, T.Y., Chen, L., Tang, Q.S., 2007. Shear wave splitting in eastern and Central China: implications for upper mantle deformation beneath continental margin. Phys. Earth Planet. Inter. 162, 73–84.

梁文宗（1990），利用地震S波分離作用探討台灣北部地殼之非均向性，國立台灣大學海洋研究所碩士論文。

吳瑋哲（2013），北越Ma River斷層帶孕震構造機制之探討研究，國立中正大學地震研究所碩士論文。