論文提要內容: 湖口斷層位於湖口台地北緣,為東北東–西南西走向,沿線有國道一號與平鎮工業區……等重要經濟建設。由於斷層之產生往往伴隨著地震,地震會造成道路的損壞,建築物的傾倒,嚴重時將會造成生命財產的損失,因此斷層之位置判斷是非常重要的。 判斷斷層位置及走向必須多方面著手,首先就地質地形研判與地表露頭之比對,再來便是使用地球物理的方法進行探測,本研究主要乃運用地電阻影像剖面法(RIP Method)進行湖口斷層之研究。 本研究區域內共施測十五條RIP測線,測線總長度達5538公尺。研究區域之淺部地層主要由高電阻率的中壢層、店子湖層與低電阻率之楊梅層所組成。由整體RIP解釋剖面可發現,於湖口台地地形崖北緣與楊梅地塹南緣間之區域,都發現有增厚之高電阻率之礫石層。而且低電阻層之分佈在此亦呈現明顯落差現象。測線十二、十三、十四地電阻剖面側向電阻率有明顯差異。由這些現像顯示出此區域之地層有明顯受到應力作用,造成地層擾動與錯動的跡象。最後將所有RIP資料與地質地形地貌進行比對,可推斷出湖口斷層位置。 ABSTRACT Taiwan is located in the Neotectonic belt along the western Pacific. Active fault is one of potential source of disaster in this island. Since the Chung-Shan Highway and Pingchen Industrial Park are quite near the Hu-Kou active fault, detecting and locating the position of the Hu-Kou active fault is one of the most important tasks for geologists and geophysicists in Taiwan. A fault can be verified by geologic mappings, geographic studies or geophysical surveys. This study is concentrated to determine the Hu-kou fault with the well-known resistivity image profiling (RIP) method. Fifteen RIP survey lines were deployed in the study area. RIP results indicate that the thickness of the high resistivity gravel layer is increased between the northern cliff of the Hu-Kou terrace and southern edge of Yangmei graben. An obvious difference of altitude is found among low resistivity zones. It may associate with the disturbance or dislocation of layers in the past. From comparisons made among results using RIP data and geologic surveys, the possible position of the Hu-Kou fault is located.