eprintid: 1858 rev_number: 10 eprint_status: archive userid: 6 dir: disk0/00/00/18/58 datestamp: 2017-03-02 11:23:36 lastmod: 2017-03-02 11:23:36 status_changed: 2017-03-02 11:23:36 type: article metadata_visibility: show creators_name: Géraud, Yves creators_name: Rosener, Michel creators_name: Surma, Fabrice creators_name: Place, Joachim creators_name: Le Garzic, Édouard creators_name: Diraison, Marc corp_creators: IPGS, UMR 7516, CNRS-UDS, école et observatoire des sciences de la Terre, institut de physique du globe de Strasbourg, université de Strasbourg, France corp_creators: IPGS, UMR 7516, CNRS-UDS, école et observatoire des sciences de la Terre, institut de physique du globe de Strasbourg, université de Strasbourg, France corp_creators: IPGS, UMR 7516, CNRS-UDS, école et observatoire des sciences de la Terre, institut de physique du globe de Strasbourg, université de Strasbourg, France; CRITT, France. corp_creators: IPGS, UMR 7516, CNRS-UDS, école et observatoire des sciences de la Terre, institut de physique du globe de Strasbourg, université de Strasbourg, France;EIFER, Germany corp_creators: IPGS, UMR 7516, CNRS-UDS, école et observatoire des sciences de la Terre, institut de physique du globe de Strasbourg, université de Strasbourg, France corp_creators: IPGS, UMR 7516, CNRS-UDS, école et observatoire des sciences de la Terre, institut de physique du globe de Strasbourg, université de Strasbourg, France title: Physical properties of fault zones within a granite body: Example of the Soultz-sous-Forêts geothermal site subjects: O subjects: RF1 subjects: SG divisions: IP4 full_text_status: none keywords: Granite; Fault zone; Porosity; Permeability; Thermal conductivity abstract: In EGS projects, fault zones are considered as the structures controlling deep flow at the reservoir scale. Using a large set of petrophysical properties (porosity, density, permeability, thermal conductivity [TC]) measured on cores collected along the EPS-1 borehole, a model of fault zone is proposed to describe them. A fault zone is a complex structure, showing different parts with different kinds of deformations and/or materials that could explain chemical and physical processes observed during fluid-rock interactions. The different parts composing the fault zone are: (1) the fault core or gauge zone; (2) the damage zone; (3) and the protolith. They are usually heterogeneous and show different physical properties. The damage zone is a potential high permeability channel and could become the main pathway for fluids if secondary minerals seal the fault core. Porosity is the lowest within the protolith, between 0.5 and 1%, but can go up to 15% in the fault zone. Permeability ranges from 10−20 m2 in the fresh granite to, at least, 10−15 m2 in the fault core, and TC ranges from 2.5 W K−1m−1 to 3.7 W K−1m−1. Finally, variations in specific surface are set over two orders of magnitude. If the lowest values usually characterize the fresh granite far from fault zones, physical properties could show variations spread over their whole respective ranges within these fault zones. date: 2010 date_type: published publication: Comptes Rendus Geoscience volume: 342 number: 7-8 publisher: Elsevier pagerange: 566-574 id_number: doi:10.1016/j.crte.2010.02.002 issn: 1631-0713 official_url: http://doi.org/10.1016/j.crte.2010.02.002 access_IS-EPOS: limited owner: Publisher citation: Géraud, Yves and Rosener, Michel and Surma, Fabrice and Place, Joachim and Le Garzic, Édouard and Diraison, Marc (2010) Physical properties of fault zones within a granite body: Example of the Soultz-sous-Forêts geothermal site. Comptes Rendus Geoscience, 342 (7-8). pp. 566-574. DOI: https://doi.org/10.1016/j.crte.2010.02.002