A Study of the hydrogeological environment of the lishan landslide area using resistivity image profiling and borehole data

作者：Lee Cheng Chao^*; Yang Chieh Hou; Liu Hsing Chang; Wen Kuo Liang; Wang Zi Bin; Chen Yi Jie

来源：Engineering Geology, 2008, 98(3-4): 115-125.

DOI：10.1016/j.enggeo.2008.01.012

• landslide
• groundwater
• resistivity
• shear zone

Resistivity linage Profiling (RIP) surveys was used to develop a lithological and hydrogeo logical model of the subsurface in the southeastern part of Lishan landslide area of central Taiwan. The bedrock consists of slate in the study area. Based on RIP and rock samples collected from boreholes results, three electrical strata are recognized: colluvium, the shear zone composed of shear gouges and shattered slate, and the undisturbed slate formation. The steep shear zone with resistivity ranging between 100 similar to 260 Omega-m, plays a crucial role in the local hydrogeological environment, because it forms a natural barrier which blocks and retains groundwater flowing down the slope. Groundwater will brim over the barrier when the water level is high. Thus the inclined groundwater table remains stable from long-term monitoring. It strongly indicates that the groundwater recharge is greater than that of discharge. Therefore, the shear zone can provide information about the optimum locations for draining the excess groundwater in-situ for slope stability consideration.
The curved basal surface of the colluvium and the weathered slate can also be discerned from the resistivity variations and boreholes data. A series of circular patterns may associate with the main slope failure which migrated upwards from the lower slope.

• 出版日期2008-5-22
• 单位中央民族大学