高雄地區地震危害潛勢微分區

Microzonation of Seismic Hazard Potential in Kaohsiung, Taiwan Area

由於2010年後，中央地質調查所將旗山斷層由存疑性活動斷層改列為高雄地區的第一類活動斷層，地震災害潛勢大為提升，需要我們對高雄地區更進一步做微分區分析、瞭解與探討。本研究使用台灣地區自1683至1899年的11個災害性地震，1900年至2013年震矩規模大於5的2065個陸上及海域淺層地震，以及旗山斷層與鄰近4條第一類活動斷層來進行高雄地區之地震危害潛勢的微分區。結果顯示地震危害潛勢最高區域是位於高雄西南部的東北區域與中部及北部區域，主要包括杉林、美濃、內門及旗山所包圍涵蓋的區域以及阿蓮、田寮、燕巢、岡山、橋頭、彌陀、梓官、大社、仁武、鳥松、鳳山、楠梓、左營、鼓山、三民、前金、新興及鹽埕所包圍涵蓋的區域，10年、30年、50年期間超過中央氣象局震度階7級的地震震度機率約分別為0-5％、5％以上、10％以上。最後與現行建築物耐震設計規範及解說之高雄地區震度劃分圖比較，則需特別注意上述地震危害潛勢高區。本研究成果可用於防範高雄地區未來地震災害的損失。

Microzonation of seismic hazard potential becomes necessary in Kaohsiung area after the Central Geological Survey upgraded the Chishan active fault from suspected fault to Category I in 2010. In this study, a catalog of 2065 shallow earthquakes occurred from 1900 to 2013 with Mw magnitudes ranging from 5.0 to 8.2, and 11 disastrous earthquakes occurred from 1683-1899, as well as Chishan active fault and 4 active faults of Category I in the vicinity are used to estimate the seismic hazard potential in Kaohsiung area for seismic microzonation. The results reveal that the highest earthquake hazard potential areas in Kaohsiung are located in the northeastern, central and northern parts of southwestern region. The probabilities of seismic intensity exceeding CWB intensity scale VII (0.4g) in 10, 30, and 50-year periods in above areas are 0-5%, greater than 5％ and 10%, respectively. Finally, by comparing with the seismic zoning map of Taiwan in current building code, we find that classification of Kaohsiung seismic zone should be pay attention to the following areas: one is in the northeastern area around Shanlin, Meinong, Neimen and Chishan. The other is in the central area around Alian, Tianliao, Yanchao, Gangshan, Ciaotou, Mituo, Zihguan, Dashe, Renwu, Niaosong, Fongshan, Nanzih, Zuoying, Gushan, Sanmin, Cianjin, Sinsing and Yancheng. Results of this study provide important information for site evaluation of critical facilities, for mitigation of regional earthquake hazards, as well as critical information for earthquake disaster management.