臺灣西北部的桃園地區位於兩大構造系統交會區域。一者是以新莊斷層為變形前緣，構造線呈東北-西南走向的褶皺逆衝系統；另一者則是以平鎮背斜為變形前緣，構造線呈東北東-西南西走向的褶皺逆衝系統，其中湖口斷層及其相關聯的湖口背斜最為顯眼，為具地震災害潛能之活動構造。大桃園地區人口數達兩百萬的，其地質特性及地震災害潛能的評估，實為當務之急。本研究將利用無人飛行載具空拍進行地形分析，加以地表地質調查、鑽井岩心對比，震測剖面及定年，繪製構造剖面，研判斷層位置、延伸範圍及活動性，並加上大漢溪溪床出露連續性良好的岩層，進行構造分析，探討兩大構造系統交會關係。同時搭配數值模擬分析，包括彈性理論的邊界元素法及離散元素法模擬斷層擴展，藉以分析湖口斷層是否為盲斷層及估算斷層面頂部深度、模擬斷層再活動的地變情形，以邊界元素法的斷層核心褶皺理論數值模擬，分析湖口背斜的形成機制，進而瞭解本區新期大地構造的演育。本研究所得之成果，預期將有助於對區域地質的瞭解、活動斷層地質敏區的劃定及斷層活動潛勢分析。 ;Two main structure systems are interlinked at the greater Taoyuan area. Hsinchuang fault is the leading edge of one system which structures trend northeast to southwest and Peicheng anticline is that of the other system which structures trend ENE to WSW. Among these structures, the Hukou fault and its related anticline are especially important in terms of their hazard potential because more than 2 million people inhabit in the greater Taoyuan area. In this study, we plan to perform well drilling to collect cores and topographic analyses to locate the fault trace along with carbon 14 dating to estimate the fault activity and characterize deformed ground using upcoming UAV aerial photographs. Core correlation will help us determine the fault existence. The structural mapping on the Dahan riverbed may resolve the relation between the two main structure systems. Furthermore, we will numerically simulate the fault propagation, Hukou anticline, earthquake-induced ground-surface deformation and deformation zone. The outcome of this study is expected to enhance the understanding of regional geology and contribute the Hukou fault zone delineation, and earthquake hazard and risk assessment.
