eprintid: 1852 rev_number: 10 eprint_status: archive userid: 6 dir: disk0/00/00/18/52 datestamp: 2017-03-02 11:16:17 lastmod: 2017-03-02 11:16:17 status_changed: 2017-03-02 11:16:17 type: article metadata_visibility: show creators_name: Ledésert, Béatrice creators_name: Hebert, Ronan creators_name: Genter, Albert creators_name: Bartier, Danièle creators_name: Clauer, Norbert creators_name: Grall, Céline corp_creators: Géosciences et environnement Cergy, université de Cergy-Pontoise,France corp_creators: Géosciences et environnement Cergy, université de Cergy-Pontoise,France corp_creators: Groupement européen d’intérêt économique exploitation minière de la chaleur, France corp_creators: Muséum national d’histoires naturelles,France corp_creators: LHyGeS (Laboratoire d’hydrologie et de géochimie de Strasbourg) (CNRS/UDS),France, corp_creators: Géosciences et environnement Cergy, université de Cergy-Pontoise,France title: Fractures, hydrothermal alterations and permeability in the Soultz Enhanced Geothermal System subjects: O subjects: RF1 subjects: SG divisions: IP4 full_text_status: none keywords: Soultz granite; Fracture network; Hydrothermal alterations; Permeability; Illite; Calcite; France abstract: Borehole studies of the Soultz-sous-Forêts granite are dedicated to deep geothermics. The hydraulic properties of the reservoir are mainly controlled by the occurrence of some altered cataclastic shear zones showing a low natural permeability characterized by the occurrence of brines. Those zones show a fracture cluster organisation with sealed fractures of various types (post-filled joints, sheared fractures, veins). The main hydrothermal deposits observed within the permeable zones are geodic quartz, carbonates, illite and more locally sulphides. The fracture wall–rocks are intensely transformed: dissolution of igneous minerals, crystallization of new minerals, porosity and permeability increase. It is important to characterize the newly-formed minerals in order to choose the reagents used to improve the permeability of the exchanger by chemical stimulations. This article represents a synthesis of the studies completed by the authors between 1990 and 2008 on the fracture networks, hydrothermal alterations and mineral crystallizations they induced and data about the flow pathways in the exchanger. date: 2010 date_type: published publication: Comptes Rendus Geoscience volume: 342 number: 7-8 publisher: Elsevier pagerange: 607-615 id_number: doi:10.1016/j.crte.2009.09.011 issn: 1631-0713 official_url: http://doi.org/10.1016/j.crte.2009.09.011 access_IS-EPOS: limited owner: Publisher citation: Ledésert, Béatrice and Hebert, Ronan and Genter, Albert and Bartier, Danièle and Clauer, Norbert and Grall, Céline (2010) Fractures, hydrothermal alterations and permeability in the Soultz Enhanced Geothermal System. Comptes Rendus Geoscience, 342 (7-8). pp. 607-615. DOI: https://doi.org/10.1016/j.crte.2009.09.011