title: Realistic molecular model of kerogen's nanostructure.
abstract: Despite kerogen's importance as the organic backbone for hydrocarbon production from source rocks such as gas shale, the interplay between kerogen's chemistry, morphology and mechanics remains unexplored. As the environmental impact of shale gas rises, identifying functional relations between its geochemical, transport, elastic and fracture properties from realistic molecular models of kerogens becomes all the more important. Here, by using a hybrid experimental-simulation method, we propose a panel of realistic molecular models of mature and immature kerogens that provide a detailed picture of kerogen's nanostructure without considering the presence of clays and other minerals in shales. We probe the models' strengths and limitations, and show that they predict essential features amenable to experimental validation, including pore distribution, vibrational density of states and stiffness. We also show that kerogen's maturation, which manifests itself as an increase in the sp(2)/sp(3) hybridization ratio, entails a crossover from plastic-to-brittle rupture mechanisms.
authors.affiliation: Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA.|〈MSE〉2, UMI 3466 CNRS-MIT, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA.
authors.forename: Colin
authors.identifier: 0000-0002-0490-2277
authors.initials: C
authors.lastname: Bousige
authors.affiliation: Institut de Science des Matériaux de Mulhouse (IS2M), UMR 7360 CNRS - UHA, 15 rue Jean Starcky, BP 2488, 68057 Mulhouse cedex, France.
authors.forename: Camélia Matei
authors.initials: CM
authors.lastname: Ghimbeu
authors.affiliation: Institut de Science des Matériaux de Mulhouse (IS2M), UMR 7360 CNRS - UHA, 15 rue Jean Starcky, BP 2488, 68057 Mulhouse cedex, France.
authors.forename: Cathie
authors.initials: C
authors.lastname: Vix-Guterl
authors.affiliation: Schlumberger-Doll Research, 1 Hampshire Street, Cambridge, Massachusetts 02139, USA.
authors.forename: Andrew E
authors.initials: AE
authors.lastname: Pomerantz
authors.affiliation: Schlumberger-Doll Research, 1 Hampshire Street, Cambridge, Massachusetts 02139, USA.
authors.forename: Assiya
authors.initials: A
authors.lastname: Suleimenova
authors.affiliation: European Synchrotron Radiation Facility, BP-220, F-38043, Grenoble Cedex 9, France.
authors.forename: Gavin
authors.initials: G
authors.lastname: Vaughan
authors.affiliation: European Synchrotron Radiation Facility, BP-220, F-38043, Grenoble Cedex 9, France.
authors.forename: Gaston
authors.initials: G
authors.lastname: Garbarino
authors.affiliation: Chemical and Engineering Materials Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA.
authors.forename: Mikhail
authors.initials: M
authors.lastname: Feygenson
authors.affiliation: Instrument and Source Division (NScD), Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA.
authors.forename: Christoph
authors.initials: C
authors.lastname: Wildgruber
authors.affiliation: Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA.
authors.forename: Franz-Josef
authors.initials: FJ
authors.lastname: Ulm
authors.affiliation: Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA.|〈MSE〉2, UMI 3466 CNRS-MIT, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA.|CINaM, CNRS/Aix Marseille Université, Campus de Luminy, 13288 Marseille cedex 09, France.
authors.forename: Roland J-M
authors.initials: RJ
authors.lastname: Pellenq
authors.affiliation: Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA.|〈MSE〉2, UMI 3466 CNRS-MIT, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA.
authors.forename: Benoit
authors.initials: B
authors.lastname: Coasne
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