摘要
本論文利用全球定位系統(Global Positioning System, GPS)地面接收機觀測電離層全電子含量(Total Electron Content, TEC)，統計分析1999-2008年全球143筆規模(M) ≥ 7.0地震期間電離層全電子含量的變化，並進一步探討不同的震源機制(focal mechanism)之異常現象。結果顯示震前7-5日期間電離層電子濃度異常減少的機會增大。此外，異常減少之現象以逆斷層與走向斷層地震最為顯著。

Abstract
In this paper, we utilize the ground based GPS receivers to measure the total electron content (TEC), and statistically analyse the ionospheic TEC variations during the periods of 143 Magnitude ≥ 7.0 earthquakes occurred between 1999 and 2008. Furthermore, we explore the anomalous phenomena of the different focal mechanisms. The results show that the probability of anomalous decrease of ionospheric electron density could lift 7-5 days before the earthquake. In addition, the phenomenon of ionospheric decreased anomaly is most significant to the reverse fault and the strike-slip fault earthquake.

參考文獻
Davies, K., 1990: Ionospheric Radio, Peter Peregrinus Ltd., London.
Dobrovolsky, I. P., Zubkov, S. I., Miachkin, V. I., 1979: Estimation of the size of earthquake preparation zones. Pure and Applied Geophysics 117, 1025–1044.
Freund, F., 2000: Time-resolved study of charge generation and propagation in igneous rocks. J. Geophys. Res., 105, 11001-11019.
Hofmann-Wellenhof, B., H. Lichtenegger, and J. Collins, 1994: GPS Theory and Practice, 3rd version, Springer-Verlag, Wien, New York.
Hunsucker, R. D., 1991: Radio Techniques for Probing the Terrestrial Ionosphere, Springer-Verlag, Berlin.
Neter, J., W. Wasserman, and G. A. Whitmore, 1988: Applied Statiatics, 3rd edition. Allyn and Bacon, Boston, USA.
Kelley, M. C., 1989: The Earth’s ionosphere. Academic Press, San Diego, USA.
Lay, Thorne and Terry C. Wallace, 1995: Modern Global Seismology. Academic Press, San Diego, USA.
Liu, J. Y., Y. I. Chen, S. A. Pulinets, Y. B. Tsai, and Y. J. Chuo , 2000: Seismo-ionospheric signatures prior to M _ 6.0 Taiwan earthquakes, Geophys. Res. Lett., 27, 3113– 3116, doi:10.1029/2000GL011395.
Liu, J. Y., Y. I. Chen, Y. J. Chou, and H. F. Tsai, 2001: Variations of ionospheric total electron content during the Chi-Chi earthquake. Geophys. Res. Lett., 28, 1383-1386.
Liu, J. Y., Y. I. Chen, H. K. Jhuang, and Y. H. Lin, 2004: Ionospheric foF2 and TEC anomalous days associated with M _ 5.0 earthquakes in Taiwan during 1997–1999, Terr. Atmos. Oceanic Sci., 15, 371– 383.
Liu, J. Y., Y. I. Chen, Y. J. Chuo, C. S. Chen, 2006: A statistical investigation of pre-earthquake ionospheric anomaly. J. Geophys. Res., 111, A05304, doi: 10.1029/2005JA011333.
Liu, J. Y., S. W. Chen, Y. C. Chen, H. Y. Yen, C. P. Chang, W. Y. Chang, L. C. Tsai, C. H. Chen, W. H. Yang, 2008: Seismo-Ionospheric Precursors of the 26 December 2006 M 7.0 Pingtung Earthquake Doublet. Terr. Atmos. Ocean. Sci., 19,751-759.
Liu, J. Y., Y. I. Chen, C. H. Chen, C. Y. Liu, C. Y. Chen, M. Nishihashi, J. Z. Li, Y. Q. Xia, K. I. Oyama, K. Hattori, and C. H. Lin, 2009: Seismoionospheric GPS total electron content anomalies observed before the 12 May 2008 Mw 7.9 Wenchuan Earthquake. J. Geophys. Res., 114, A04320, doi:10.1029/2008JA013698.
Lu, Y and J. A. Bean, 1995: On the sample size one-sided equivalence of sensitivities based upon McNemar’s test. Statistics in Medicine 14, 1831-1839.
Opperman, BDL, 2007: Reconstructing Ionospheric TEC over South Africa Using Signals from a Regional GPS Network. Doctor Thesis of Philosophy of Rhodes University. South Africa.
Shearer, P. M., 1999: Introduction to Seismology. Cambridge, New York.
Ya’acob, Norsuzila, M. Abdullah, M. Ismail, 2008: Determination of GPS Total Electron Content using Single Layer Model (SLM) Ionospheric Mapping Function. IJCSNS, VOL.8 No.9.
Yeh, K. C., and C. H. Liu, 1972: Theory of Ionospheric Waves. Academic Press, New York.
林鈺翔, 利用全球定位系統觀測電離層地震前兆, 碩士論文, 國立中央大學太空科學研究所, 中壢, 2004.
莊皓琨, 台灣地區地震前之電離層電子濃度異常, 碩士論文, 國立中央大學太空科學研究所, 中壢, 2004.
蔡和芳, 全球定位系統觀測電離層赤道異常之研究, 博士論文, 國立中央大學太空科學研究所, 中壢, 1999.
劉程艷, 基於GPS研究大地震前震中上空電離層全電子濃度異常, 碩士論文, 北京工業大學, 北京, 2008.