Quantitative Analysis of Experimental and Synthetic Microstructures for Sedimentary Rock

TL;DR

This study compares experimental and theoretical microstructures of Fontainebleau sandstone using microtomography and models, revealing similarities in porosity but differences in connectivity and anisotropy, informing future model improvements.

Contribution

It provides a quantitative comparison between experimental microstructure and three theoretical models, highlighting their similarities and differences in microstructural properties.

Findings

Porosity closely matches across models and experiment.

Two models replicate the two-point correlation function of the real sample.

Significant differences in connectivity and anisotropy were observed.

Abstract

A quantitative comparison between the experimental microstructure of a sedimentary rock and three theoretical models for the same rock is presented. The microstructure of the rock sample (Fontainebleau sandstone) was obtained by microtomography. Two of the models are stochastic models based on correlation function reconstruction, and one model is based on sedimentation, compaction and diagenesis combined with input from petrographic analysis. The porosity of all models closely match that of the experimental sample and two models have also the same two point correlation function as the experimental sample. We compute quantitative differences and similarities between the various microstructures by a method based on local porosity theory. Differences are found in the degree of anisotropy, and in fluctuations of porosity and connectivity. The stochastic models differ strongly from the real sandstone in their connectivity properties, and hence need further refinement when used to model transport.