Multiscale heterogeneity in low permeability reservoirs: An integrated framework for characterization, quantification, and scale transfer
Abstract
Low permeability reservoirs contain pore-throat systems spanning nanometers to kilometers. Their storage capacity, flow behavior, and development response therefore depend on scale. Homogeneous medium models cannot adequately represent this heterogeneity or transfer pore scale mechanisms to reservoir scale predictions. This study synthesizes methods for characterizing and quantifying heterogeneity and transferring information across scales. It distinguishes three genetic controls: Sedimentation, diagenesis, and tectonic deformation. Characterization methods are compared by measurement principle, resolution, and sampling volume. Fractal analysis, geostatistics, and digital core modeling are assessed as sources of quantitative descriptors. A published tight sandstone example illustrates data selection, cross calibration, pore scale indicators, and the transfer of core measurements to dynamic model inputs. Transferable mechanisms are distinguished from reservoir specific parameters because pore geometry and dominant flow processes vary among sandstone, shale, carbonate, and fractured systems. This study identifies four key research bottlenecks: Cross method calibration, physically consistent nonlinear upscaling, dynamic heterogeneity, and limited experimental and computational coverage. Priorities are uncertainty aware data integration, flow linked indicators, coupled dynamic validation, and efficient multiscale modeling. A unified research framework integrating characterization, quantification, and cross scale transfer is established. The findings provide a theoretical reference for microscopic pore-throat flow analysis and macroscopic dynamic prediction, as well as guidance for the efficient development of low permeability reservoirs.
Document Type: Invited review
Cited as: Li, Y., Hui, G., Pi, Z., Chen, Z., Li, J., Cai, J. Multiscale heterogeneity in low permeability reservoirs: An integrated framework for characterization, quantification, and scale transfer. Advances in Geo-Energy Research, 2026, 22(3): 201-214. https://doi.org/10.46690/ager.2026.12.01
DOI:
https://doi.org/10.46690/ager.2026.12.01Keywords:
Low permeability reservoir, multiscale heterogeneity, pore structure, upscaling, nonlinear flow, integrated frameworkReferences
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Copyright (c) 2026 Ye Li, Gang Hui, Zhiyang Pi, Zhangxin Chen, Jing Li, Jianchao Cai
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