Mesoscale structure, mechanics, and transport properties of source rocks’ organic pore networks
Name
12365.full.pdf
Description
Published version
Size
1.45 MB
Format
Unknown
Checksum (MD5)
d59ca45957f205f48e46a6199fdc903c
Author(s)
Berthonneau, Jeremie
Obliger, Amaël
Valdenaire, Pierre-Louis
Grauby, Olivier
Ferry, Daniel
Chaudanson, Damien
Levitz, Pierre
Kim, Jae Jin
Ulm, Franz-Josef
Pellenq, Roland J.-M.
Date Issued
November 2018
Journal
Proceedings of the National Academy of Sciences
Publisher
National Academy of Sciences
Version
Final published version
Abstract
© 2018 National Academy of Sciences. All rights reserved. Organic matter is responsible for the generation of hydrocarbons during the thermal maturation of source rock formation. This geochemical process engenders a network of organic hosted pores that governs the flow of hydrocarbons from the organic matter to fractures created during the stimulation of production wells. Therefore, it can be reasonably assumed that predictions of potentially recoverable confined hydrocarbons depend on the geometry of this pore network. Here, we analyze mesoscale structures of three organic porous networks at different thermal maturities. We use electron tomography with subnanometric resolution to characterize their morphology and topology. Our 3D reconstructions confirm the formation of nanopores and reveal increasingly tortuous and connected pore networks in the process of thermal maturation. We then turn the binarized reconstructions into lattice models including information from atomistic simulations to derive mechanical and confined fluid transport properties. Specifically, we highlight the influence of adsorbed fluids on the elastic response. The resulting elastic energy concentrations are localized at the vicinity of macropores at low maturity whereas these concentrations present more homogeneous distributions at higher thermal maturities, due to pores’ topology. The lattice models finally allow us to capture the effect of sorption on diffusion mechanisms with a sole input of network geometry. Eventually, we corroborate the dominant impact of diffusion occurring within the connected nanopores, which constitute the limiting factor of confined hydrocarbon transport in source rocks.
MIT Department
MultiScale Materials Science for Energy and Environment, Joint MIT-CNRS Laboratory
Massachusetts Institute of Technology. Department of Civil and Environmental Engineering
Terms of Use
Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use.
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1073/pnas.1808402115
