2D Forward And Inverse Research With Topography Of CSAMT Method

CSAMT is a kind of geophysics exploration with high efficiency, which can be applied in many fields and will has further development. this paper have discussed the topography influence in the data interpretation of CSAMT with many research methods such as numerical modeling and contrastive analysis etc.Firstly, forward process has been carried out in the case of2D model with just topography, such as chine, valley, slope, then another case of2D model of topography with different objects beneath the surface. The modeling results obviously illustrate the characteristic and regulation of apparent resistivity in the method of CSAMT. it is demonstrated as TM pattern is more likely to influenced by topography then TE pattern, chine with high underground resistivity or valley with low underground resistivity are more sensitive to topography; The larger of terrain-tilt angle, the much influence to apparent resistivity. It also indicates that the interference from topography will not only bring false anomaly, but also cover the real response from abnormal object, as a result, cause a definitely wrong interpretation. Thus, the influence of topography to resistivity of TM pattern in CSAMT can never be neglected.Secondly, do2d model inverse with topography added to the data acquired from field, in which conclusion of forward should be took in consideration, the outcome will better reflect the importance of inverse process with topography.Using Matlab software to calculate a plate graph with the variable of distance of separation between receiver and transmitter and apparent resistivity in. the condition of ID CSAMT, so as to provide reference for seeking absolute, the predecessor just transferred a rough statistical result and this paper can be used to instruct field acquisition, during the acquiring in the field, knowing about the resistivity of detective area can help us easily find the far area with the kelp of template chart.