本研究對車籠埔斷層南段的地表破裂進行二維的電阻率影像剖面探測，了解斷層地表下電阻率分布，並推測斷層在地表下的地層分布及構造形貌，獲得以下結論：（１)斷層所處地形及地層的特性，可將九二一地震斷層在竹山南部分段，北為車籠埔斷層，南則為大尖山斷層的起點。（２）振興地區表層為厚15公尺麓山帶堆積層，電阻率40-60 Ω．m。錦水頁岩電阻率10-60 Ω．m。下盤的礫石層電阻率100-600 Ω．m，與下伏錦水頁岩為不整合接觸。斷層傾角60-70度向東。（３）濁水地區、水底寮地區和他里塭地區表層為礫石層，厚度10-20公尺不等，電阻率100-5000 Ω．m。錦水頁岩電阻率5-60。下盤礫石層近斷層受擠壓增厚，電阻率100-2400，隨深度增加漸變為含泥礫石層，電阻率10-300。斷層傾角為40-80度向東。（４）外埔子地區表層分布厚約2-5公尺局部不連續的礫石層，電阻率為100-1000 Ω．m。錦水頁岩電阻率5-60 Ω．m，下盤之礫石層電阻率100-300 Ω．m。此處斷層出露所在的東埔蚋溪局部沿斷層發育。（５）竹山地區顯示表層礫石層厚度5-20公尺不等，電阻率80-800 Ω．m。錦水頁岩電阻率40-60 Ω．m，下盤之礫石層電阻率100-2000 Ω．m，斷層傾角為60-80度向東。（６）抄封地區深度60公尺以上為階地礫石層，電阻率100-800 Ω．m，下伏為卓蘭層，電阻率10-80 Ω．m，兩地層以不整合接觸。測線J-J’水平位置32公尺與88公尺處皆為地形高起階地，為曾經錯動過的斷層帶，斷層面視傾角為60-70度向東。（７）林頂地區表層為厚5-15公尺不等的階地礫石層，電阻率100-2000 Ω．m，下伏為桂竹林層，電阻率5-60Ω．m。斷層傾角為40-70度向東。 The resistivity image profiling methed is were used to investigate the feature of the electric resistivity structures ane the subsurface structure of southern segment of the Chelungpu fault. Several conclusions can be drawn as follows：(1)According to the geoelectric characteristic of the formations was able to paragraph of the Chinshi south on the 921 earthquake fault. Northern segment was Chelungpu fault. Southern segmernt was starting point of Dajianshan fault.(2)Detritus of foothill has a thickness of about 15 meters and a resistivity of about 40-60 Ω．m in the surface of Jennshing area. Resistivity of Chinshui Shale is about 10-60 Ω．m. Resistivity of Gravel formation of footwall is about 100-600 Ω．m. Chinshui Shale does not have uniform contact within its Gravel formations. The fault dips eastward at an angle of about 60-70 degrees. (3)Gravel formation thickness is about 10-20 meters and resistivity is about 100-5000 Ω．m in surface of Jwoshoei, Shoeidiliau and Taliuen area. Resistivity of Chinshi Shale is about 5-60 Ω．m. Gravel formation of the footwall near the fault has thickened due to pressure and its resistivity is 100-2400 Ω．m. Deeper into the formation, the gravel turns oozy and the resistivity is 10-300. The fault dips eastward at an angle of about 40-80 degrees.(4)Waipuzi area thickness is about 2-5 meters of non-continuous gravel formation, Resistivity is 100-1000 Ω．m. Resistivity of chinshi shale is about 5-60. Resistivity of Gravel formation at footwall is 100-300 Ω．m. This fault zone appears at Dongpuna river part of it is growing.(5)Gravel formation thickness is about 5-20 meters and resistivity is about 80-800 Ω．m in surface of Chushan area. Chinshui shale is about 40-60 Ω．m. Resistivity of Gravel formation at footwall is 100-2000 Ω．m. The fault dips eastward at an angle of about 60-80 degrees.(6)The area depth 60m or higher is terrace deposit of Chaofeng, resistivity is about 100-800 Ω．m. Below 60m depths is cholan formation, resistivity is about 10-80 Ω．m. The two areas are unconformity contact. The measurable line J-J’. Horizontal line between 32m and 88m are terraces. Used to be a fault zone. The fault apparent dips eastward at an angle of about 60-70 degrees. (7)Gravel formation thickness is about 5-15 meters terrace deposits and resistivity is about 100-2000 Ω．m in surface of Linding area. Below is kueichulin formation, resistivity is 5-60 Ω．m. The fault dips eastward at an angle of about 40-70 degrees.
