Modeling of Bulk Kerogen Porosity: Methods for Control and Characterization
Shale gas is an unconventional source of energy, which has attracted a lot of attention during the last years.
Kerogen is a prime constituent of shale formations and plays a crucial role in shale gas technology. Significant experimental effort
in the study of shales and kerogen has produced a broad diversity of experimentally determined structural and thermodynamic
properties even for samples of the same well. Moreover, proposed methods reported in the literature for constructing realistic
bulk kerogen configurations have not been thoroughly investigated. One of the most important characteristics of kerogens is their
porosity, due to its direct connection with their transport properties and its potential as discriminating and classifying metric
between samples. In this study, molecular dynamics (MD) simulations are used to study the porosity of model kerogens. The
porosity is controlled effectively with systematic variations of the number and the size of dummy LJ particles that are used during
the construction of system’s configuration. The porosity of each sample is characterized with a newly proposed algorithm for
analyzing the free space of amorphous materials. It is found that, with moderately sized configurations, it is possible to construct
percolated pores of interest in the shale gas industry.