Discussion on MT data acquisition technique and processing method in Zhenba area
Yang Zhen-sheng1,2, Gu Jin-cai2
1. Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing City,100029,China;
2. Sixth Brigade of Geophysical Prospecting,East-China Petroleum Administration,Nanjing City,Jiangsu Province,210009,China
Abstract：The Zhenba area,situated in hinterland of Dabashan Mountain and affected by high and steep mountains and complex underground geologic structures,is characterized by lower oil/gas exploration degree and poorer exploration effect.Through analyzing and studying the experimental data of influence of such parameters as electrode spacing,configuration,array and slope on MT data,the paper discussed MT acquisition method and production factors suitable for the topographic feature in the area.In combination with study of 2D forward simulation,the paper also carried out the analysis and discussion on the reasons of "over-phase" resulted from the variation characters of MT curves in complex surface types of mountains,influence of subsurface non-uniform bodies,influence of topographic inequality and interference of geologic structure;highlighted the importance of MT data preprocessing and analysis of physical property;presented integrative use of limit geologic,seismic and drilling data in high and steep complex mountains and constrain model-building to carry out the inversion imaging of 2D layered medium,thus providing reliable basic data for regional area-selected evaluation.
