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Computational Geosciences

, Volume 22, Issue 4, pp 1083–1091 | Cite as

Apparent permeability and representative size of shale: a numerical study on the effects of organic matter

  • Jiangfeng Cui
  • Long Cheng
  • Lei Li
Original Paper
  • 181 Downloads

Abstract

The impact of organic matter on the flow capacity of shale oil rocks is presumably significant, and the knowledge about the representative size is fundamental for the upscaling studies. The error of the experimentally determined permeability values is comparable with the contribution of kerogen to shale permeability, instead a 2D numerical model is employed to explore the normalised equivalent permeability and the representative elementary area (REA) of shale oil rocks in detail incorporating the effects of kerogen. The discussions on the normalised equivalent permeability and the REA are based on the statistical average and standard deviation from 1000 different runs, respectively. The inorganic permeability heterogeneity is introduced based on the assumption of a lognormal pore size distribution and the Monte Carlo sampling method. The effects of kerogen geometric characteristics are incorporated by putting forward several representative cases for comparison. The effects of the organic permeability contrast (ratio of permeability to the inorganic permeability with no heterogeneity), total organic carbon (TOC, volume fraction), inorganic permeability heterogeneity and kerogen geometric characteristics on the normalised equivalent permeability (ratio of the intrinsic equivalent permeability to inorganic permeability with no heterogeneity) and the REA are discussed comprehensively. This work can provide a better understanding of shale oil rocks at the micrometer scale.

Keywords

Normalised equivalent permeability Representative elementary area Shale oil Kerogen Numerical study 

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Notes

Acknowledgments

We express thanks to Professor Zhou Shengtian for discussion.

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Copyright information

© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  1. 1.School of Petroleum EngineeringChina University of Petroleum (East China)QingdaoChina
  2. 2.School of GeosciencesChina University of Petroleum (East China)QingdaoChina

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