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Analyzed from the 5 boreholes on the Hukou coast in Hsinchu County, the lateritic terrace deposits on the Hukou Fault footwall has a 110 m elevation difference against the lateritic conglomerate deposits of Hukou borehole 1, 5 and the top of the Fengling Hills. However, it is still undetermined whether the 40 m lateritic conglomerate of the borehole belongs to the Chungli Formation or the Dianzihu Formation. If it belongs to the Dianzihu Formation, then the elevation difference on the both sides of the fault would be 110 m.
The vertical deformation rate of the Hukou borehole 2 and 4 (on the hanging wall) is estimated to be between 1mm/yr to -1mm/yr. There are no specific dating data on the Hukou borehole 1 and 5, which is on the footwall of the fault, so the deformation rate cannot be calculated. However, from north of Hsinwu in Taoyuan County to the coast in Dayuan, which is 10-20 km away from the Hukou Fault, has an Holocene algal reef outcrop (7600-3800 yr BP). If the vertical deformation rate is thus calculated, then it would still be between 1mm/yr to -1mm/yr. Based on the seismic reflection profile referred from Ruei Chyuan Shih et al. (2009), the Hukou anticline is a fault-bend fold structure resulted from the curve of the Hukou Fault. The surface geological data and the seismic reflection profile from CPC Corporation, Taiwan shows that the Hukou anticline possibly runs from the Fenggang Hills southwestwards to the Touchien River alluvial plain then into the ocean. The anticline axis is mostly located on the northern coast of the Touchien River. This study conducted on the coastal plain shows that the hanging wall near the Hukou Fault is slightly uplifted (~0.1 mm/yr) But near the Touchien River outfall (Nanliao Elementary School borehole) the uplift rate is higher, 1.7¡Ó0.8 mm/yr. This area happens to be near the Hukou anticline axis.
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