Fracture is the important storage space and seepage channel of fluid in fractured reservoirs. The fractured reservoirs are obviously electric anisotropic. The array lateral log has not only higher vertical resolution but provides more information for recognizing fracture and effectively determining fracture parameters of reservoirs. By using the plate model of parallel fracture group, a formation model with electric anisotropy is established. The three-dimensional finite element method is used to simulate the response of array lateral log under different fracture dip and porosity conditions. Numerical simulation shows that when fracture spacing is small, array lateral log of fracture group shares the same logging response with the formation of macroscopic electric anisotropy. On the one hand, with fracture porosity increasing, the response of array lateral log decreases. The apparent resistivity of array lateral log is approximately inversely linear to fracture porosity. The difference between the deep and shallow responses is controlled by fracture occurrence. When the fracture angle is low the difference is small and when the angle is high there turns out to be a positive difference. Meanwhile, when fracture is horizontal, the response of array lateral log mainly reflects the resistivity parallel to fracture, and with the dip increasing, the effect of the vertical resistivity becomes greater, which results in the increasing response of array lateral log. The good correlation between array lateral log and fracture parameters indicates the array lateral log can be used to determine fracture parameters. According to the nonlinear least square method, the response of array lateral log is inverted by using Marquardt algorithm. The inverted results, both fracture porosity and dip, show an excellent match with parameters in real formation model. This in result will promote the application of the novel high resolution array lateral log in formation fracture evaluation.
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