Geoelectrical structure of Taiwan from magnetotelluric data
Speaker: Hsiu-Po Yeh
Abstract
After Chen et al. (1998), there was no complete view of deep geoelectrical structure in Taiwan area. The purpose of this study is to understand the geoelectrical structure of Taiwan. We used 1D-Occam inversion to get the 1D-Models and applied the depth of investigation index (DOI) method proposed by Oldenburg and Li (1999) to find the high resolution part of the results to avoid the misleading interpretation. In this study, the low DOI value (R<0.5) indicates the high resolution of the 1D-models. The observed data and the inversion results show that the distribution of resistivity anomalies is consistent with topographic map, geologic map, active fault map and magnetic anomaly map. Comparing with 2D-Models (Bertrand et al., 2009), the 1D-Occam inversion generates the similar results at North-Line and South-Line. But the 1D-Models are much different to the 2D-Model at Central-Line. The reason could be the different data set.
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台灣活斷層圖，國立中央大學應用地質研究所工程地質與防災科技研究室整理。