Investigating of lake bottom and fault structure by using Resistivity Imaging Profiling

• Main Authors: Chi-Pin Lin, 林啟斌
• Other Authors: Chieh-Hou Yang
• Format: Others
• Language: zh-TW
• Published: 1999
• Online Access: http://ndltd.ncl.edu.tw/handle/65875073286575693802

碩士 === 國立中央大學 === 地球物理研究所 === 87 === Investigating of underwater and fault structure by using resistivity imaging profiling Chi-Pin Lin Abstract Direct current (dc) resistivity survey with different electrode arrays was used to analyze geoelectrical layers under the bottom of Chung-Dah Lake and also the features of Hsin-Chun fault. Qualitative and quantitative interpretation of the data, some conclusion are drawn as follows : 1. Both survey results carried out on water surface and along water bottom are comparable; referred to local geology, the electrical layers under the lake bottom are lateriate and gravel. 2. The inversion result of the data collected on the water surface indicates that the resistivity of water body is comparable to the direct measurement with a Wenner array from the water body. However, the inversion result of the data obtained from water bottom does not show the existence of the water body. This may due to the electrode spacing is greater than the water depth , thus the resolution of the water body is decreased. 3. Resistivity imaging profiles obtained from both pole-pole and pole-dipole methods indicate the existence of the HSIN-Chun fault. However, pole-pole resistivity imaging profiling has better lateral resistivity changes of the fault. Pole-dipole resistivity result can give the dip of the fault, combined these two survey techniques, it can improve the quality of field data. 4.Compared the forward and reverse pole-dipole resistivity imaging surveys, it can reduce the effect of the asymmetry of the array on resistivity measurements and improve the reliability of the final result.