2008-05-092024-05-13https://scholars.lib.ntu.edu.tw/handle/123456789/642653摘要：近10年科技發展及觀測儀器的進步，對於活動斷層及地震活動的監測，有更準確及更有效率的方法，此新研究方法涵蓋不同的觀測週期和不同尺度的地殼變形。本研究藉由經濟部中央地質調查所所建立的44個連續記錄全球衛星定位系統（GPS）與位於曾文水庫南站(RST)、曾文水庫北站(RNT)與甲仙十八灣站(ECT)等3個井下應變儀監測七條斷層(山腳斷層、新城斷層、屯子腳斷層、彰化斷層、九芎坑斷層、新化斷層與後甲里斷層)之活動性。台灣近年來運用各種儀器的輔助來進行長短不同週期的觀測，如移動式GPS觀測、合成孔徑雷達干涉(InSAR)、地震儀，但在觀測頻率之涵蓋面上和微小應變的能力上仍有不足，而井下應變儀和連續GPS觀測剛好可以補上這個地震儀與移動式GPS觀測不足之處。因此1999年集集地震後政府投入大量的資源在地震科學上的研究，建立全島的全球衛星定位系統連續觀測網和部分的井下應變儀觀測站。本計畫的主要執行重點為：（1）分析連續44個連續GPS測站及三個井下應變儀之時間序列以得到觀測站異常變動；（2）藉由長期觀測推估研究地區GPS速度場變化並進一步瞭解應力累積狀況；（3）藉由基線變化瞭解主要活動斷層的變化行為並分析與地震之關聯；（4）利用數值分析之模擬斷層型態、滑移速率與斷層參數並可推估最大可能之地震規模；（5）經由重覆地震推估深部滑移速率並與井下應變儀和連續GPS觀測記錄比較；（6）配合多樣觀測資訊瞭解地震發生前的異常現象，並評估地震前兆的可能性；(7) 建置井下應變儀資料庫。因此本計畫的執行，旨在結合水準與GPS測量與井下應變儀，觀測對研究後近斷層的活動潛勢的監測，結合地質構造、數值模擬和斷層活動度的研究，期能提供近斷層活動性及其潛勢、孕震過程、發震構造、震源力學和可能地震前兆的重要資訊。<br> Abstract: On the progress of science and technology for instrument renewal toward the research of the earthquake activity in recent 10 years, the study of the earthquake potential and seismotectonics is more accurate and more efficient. These new methods provide different time spans of observation and the ability of detection of minor crustal deformation. This study uses the 44 continuous-recording GPS stations and 3 borehole strainmeters (RNT, RST and ECT) established by Central Geological Survey to monitor the activity of seven major faults (Shanchiao fault, Hsincheng fault, Tuntzechiao fault, Changhua fault, Chiuchungkeng fault, Hsinhua and Houchiali fault) in Taiwan. Various methods of observations such as survey-mode GPS, InSAR and seismometers which cover different frequency of observation and sensitivity of deformation rate are applied to this scientific goal. However, the measurements and observations from these methods could be further improved by continuous GPS and borehole strainmeters due to the coverage of frequency of observation and sensitivity of crustal deformation. Thus, after 1999 Chi-Chi earthquake, the government devotes a great deal of resource to establish an island-wide continuous recording GPS network and some local networks of borehole strainmeters. The main goals of this project are (1) analysis of time series of continuous GPS and borehole strainmeters for the anomaly of signals from crustal deformation; (2) the crustal strain accumulation from GPS velocity filed; (3) characterization of activities of seven major active faults and earthquake based on the baseline change of continuous GPS stations; (4) assessment of earthquake potential based on the subsurface fault geometry, fault parameters, slip rate along the fault patches from numerical modeling; (5) characterization of repeating earthquake sequences and comparison with the measurement of continuous GPS and borehole strainmeters; (6) assessment of earthquake potential and precursor based on the possible signals of crustal strain; (7) build-up of database for the borehole strainmeters. Thus, the performance and aim of this project combine the precise leveling, GPS and borehole strainmeters in order to monitor the activity of major faults. Furthermore, we will combine the geological data, numerical modeling and the analysis of fault activity to provide the valuable information of near-field fault activity, seismogenic structures and process, mechanics of seismotectonics and possible precursors of big earthquakes.全球衛星定位系統基線變化連續觀測站時間序列分析數值分析井下應變儀重覆地震GPSBaseline changeCGPSTime series analysisNumerical analysisBorehole StrainmeterRepeating Earthquakes