Petroleum Science

, Volume 8, Issue 1, pp 11–16 | Cite as

Response characteristics of array lateral logs and their primary inversion in reservoirs with fracture-induced anisotropy

Article

Abstract

In order to identify fractured reservoirs and determine their fracture parameters with a high definition array laterolog, we built a fracture-induced anisotropic formation model with a parallel fracture group. The three-dimensional finite element method is used to simulate the responses of the array laterolog, and then the primary inversion method is utilized. Numerical simulation shows that when the fracture spacing is small, the array laterolog response of the fracture group is the same as that of a formation with macroscopic electrical anisotropy. The apparent resistivity of the array laterolog is approximately inversely proportional to fracture porosity. The anisotropy depends on the fracture porosity in the fractured formation, which accordingly results in response variation of the array laterolog. The higher the fracture dip, the larger the apparent resistivity. When the fracture dip is low the difference between the deep and shallow apparent resistivities is small, and when the dip is high the difference turns out to be positive. The fracture parameters were inverted using the Marquardt non-linear least squares method. The results, both fracture porosity and dip show a good match with parameters in the actual formation model. This will promote the application of the array laterolog in evaluating fractured reservoirs.

Key words

Fracturing anisotropic reservoir fracture dip fracture porosity array laterolog 

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Copyright information

© China University of Petroleum (Beijing) and Springer-Verlag Berlin Heidelberg 2011

Authors and Affiliations

  • Shaogui Deng
    • 1
  • Yiren Fan
    • 1
  • Zhiqiang Li
    • 2
  • Qingtao Sun
    • 1
  1. 1.School of Geo-resources & InformationChina University of PetroleumShandongChina
  2. 2.China Research Institute of Radio Wave PropagationHenanChina

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