Fractal pore structure of sedimentary rocks: Simulation by ballistic deposition

Abstract

[1] Experimental studies show that porous sedimentary rocks have a fractal pore-grain interface. The bidisperse ballistic deposition model (BBDM) generates a porous structure by computer simulation. The model is able to reproduce the behavior of several macroscopic properties of sedimentary rocks quite well. In the present paper we show that the microstructure of the pore space created in BBDM is also realistic. Two-point correlations of the pore space agree qualitatively with results for real rocks, and the sample spanning pore has a fractal dimension in the range 2.29-2.99 for different porosities. We also study diffusion in the pore space by a random walk and show that it is anomalous at low porosities.

The relationship between fractal properties of solid matrix and pore space in porous media

“…These approaches include the generation of regular pore networks (e.g., Berkowitz and Ewing, 1998), networks developed according to morphologically determined parameters of a soil (Vogel, 2000), the simulation of sedimentation processes (Dutta and Tarafdar, 2003), and the use of fractal models. For the latter, a minimum requirement for the applicability of the model is that the natural porous medium exhibits a self-similar scaling, described by its fractal dimension.…”

A simulation study of reactive flow in 2-D involving dissolution and precipitation in sedimentary rocks

“…We refer to this model as the Relaxed Bidisperse Ballistic Deposition Model (RBBDM). In an earlier study (Dutta and Tarafdar, 2003), the authors have shown that the sample attains a constant porosity only after a sufficient number of grains (depending on sample size) have been deposited to overcome substrate effects. Here, a 128 Â 1000 size sample was generated.…”

“…(2). The details of the generation of the porous rock sample are given in Dutta and Tarafdar (2003) and Sadhukhan et al (2007). Above the percolation threshold, the simulated structure has at least one connected pore structure.…”

“…In this paper we propose a model for the simulation of reactive flow in sedimentary rock samples generated by the 'Relaxed Bidisperse Ballistic Deposition Model' (RBBDM) (Dutta and Tarafdar, 2003;Sadhukhan et al, 2007) with the aim to study the effect of variation of different flow parameters like Peclet number, Damkholer number, concentration of reactive species and pressure on dissolution and precipitation reactions through their manifestation on rock properties like porosity and permeability. Our model of reactive flow is done on a 2-D porous rock whose porosity can be varied to match that of a real rock.…”

Simulation of diagenesis and permeability variation in two-dimensional rock structure

“…Much work has been done in this direction (Dasgupta et al . 2000; Dutta & Tarafdar 2003; Manwart et al . 2000; Øren & Bakke 2003; Pape et al .…”