Jeanne Vidal

Etudiant en thèse

 

PhD thesis

Subject

Hydrothermal alteration associated with zones of fractures at the interface between sedimentary cover and granitic basement in the Upper Rhine Graben. Application to geothermal wells at Rittershoffen (Alsace, France). 

Abstract

The knowledge of the fracture network is a key challenge to understand the fluid circulation through a reservoir. The aim of this PhD project is to investigate the natural fracture network that channelized the hydrothermal circulations into two deep wells GRT-1 and GRT-2 at Rittershoffen (Alsace, France) that intersect Triassic sandstones and altered granitic basement in the framework of an industrial geothermal project.

The structural study of the fracture network was based on acoustic image logs correlated with standard geophysical logs, whereas the mineralogical study was based on cutting samples. Permeable fracture zones of wells at Rittershoffen present an asymmetrical organization of permeability. Open fractures at the borehole scale act as fluid pathways surrounded by halos of hydrothermal alteration. These fracture zones are associated with local thermal anomalies in the temperature profiles at the borehole scale. Occurrences of heterogeneous illitic minerals could be a good indicator to prospect zones of actual and past circulations at the borehole scale.

This geological study develops towards a model of hydrothermal well with favorable connections to the fractured reservoir without stimulation operations.

Keywords

natural fractures, acoustic image logs, hydrothermal alteration, deep geothermal site, Rittershoffen, Upper Rhine Graben. 

Supervisors

Jean Schmittbuhl (Université de Strasbourg, CNRS)
Hubert Whitechurch (Université de Strasbourg, EOST)
Albert Genter (ES-Géothermie)

Funding

The PhD thesis is co-funded by the ADEME, the French Agency for Environment and Energy, and the Labex G-Eau-Thermie Profonde, a scientific research project co-funded by the French government under the program “Investissements d’Avenir”.

Contract beginning and end

October 2014 – October 2017

 

Scientific contributions

Publications

Vidal J. & Genter A. (2018). Overview of naturally permeable fractured reservoirs in the central and
southern Upper Rhine Graben: Insights from geothermal wells, Geothermics, 74, 57-73, https://doi.org/10.1016/j.geothermics.2018.02.003

Vidal J., Patrier P., Genter A., Beaufort D., Dezayes Ch., Glass C., Lerouge C., Sanjuan B. (2018). Clay minerals related to the circulation of geothermal fluids in boreholes at Rittershoffen (Alsace, France), Journal of Volcanology and Geothermal Research, 349, 192-204, doi: 10.1016/j.jvolgeores.2017.10.019 

Vidal J., Genter A., Chopin F. (2017). Permeable fracture zones in the hard rocks of the geothermal reservoir at Rittershoffen, France, Journal of Geophysical Research: Solid Earth, 122, 4864-4887, doi: 10.1002/2017JB014331 

Baujard C., Genter A., Dalmais E., Maurer V., Hehn R., Rosillette R., Vidal J., Schmittbuhl J. (2017). Hydrothermal Characterization of wells GRT-1 and GRT-2 in Rittershoffen, France: Implications on the Understanding of Natural Flow Systems in the Rhine Graben, Geothermics, 65, 255-268, doi: 10.1016/j.geothermics.2016.11.001

Vidal J., Genter A., Schmittbuhl J. (2016). Pre- and post-stimulation characterization of geothermal well GRT-1, Rittershoffen, France: insights from acoustic image logs of hard fractured rock, Geophys. J. Int., 206(2), 845-860, doi: 10.1093/gji/ggw181

Vidal J., Genter A., Schmittbuhl J. (2015). How permeable fractures in the Triassic sediments of Northern Alsace chracaterize the top of hydrothermal convective cells? Evidences from Soultz geothermal boreholes (France), Geothermal Energy Journal, Special Issue: Characterization of Deep Geothermal Systems, 3(8), doi:10.1186/s40517-015-0026-4

Extended Abstracts
  • Oral presentation

Vidal J., Patrier P., Genter A, Beaufort D. (2017). Occurrences of clay minerals in permeable fracture zones in the granitic basement of geothermal wells at Rittershoffen, France, 42nd Workshop on Geothermal Reservoir Engineering, February 13 - 15 2018, Stanford University, California, USA

Vidal J., Genter A., Chopin F., Dalmais E. (2016). Natural fractures and permeability at the geothermal site Rittershoffen, France, European Geothermal Congress, September 19 - 26 2016, Strasbourg, France

Hehn R., Genter A., Baujard C., Vidal J. (2016). Stress field rotation in the EGS well GRT-1 (Rittershoffen, France), European Geothermal Congress, September 19 - 26 2016, Strasbourg, France

Genter A., Baujard C., Cuenot N., Dezayes Ch., Kohl Th., Masson F., Sanjuan B., Scheiber J., Schill E., Schmittbuhl J., Vidal J., (2016). Geology, Geophysics and Geochemistry in the Upper Rhine Graben: the frame for geothermal energy use, European Geothermal Congress, September 19 - 26 2016, Strasbourg, France

Vidal J., Ulrich, R., Whitechurch H., Genter A., Schmittbuhl J., Dalmais E., Girard-Berthet V. (2016). Hydrothermal alteration of the hidden granite in the geothermal context of the Upper Rhine Graben, 41st Workshop on Geothermal Reservoir Engineering, February 22 - 24 2016, Stanford University, California, USA

Genter A., Vidal J., Baujard C., Dalmais E.,  Schmittbuhl J. (2015). Permeability in deep-seated granitic rocks: lessons learnt from deep geothermal boreholes in the Upper Rhine Graben, Vingtièmes journées techniques du Comité Français d’Hydrogéologie de l’Association Internationale des Hydrogéologues - Aquifères de socle : le point sur les concepts et les applications opérationnelles, June 2015, La Roche-sur-Yon, France

Vidal J., Genter A., Duringer Ph., Schmittbuhl J. (2015). Natural permeability in fractured Triassic sediments of the Upper Rhine Graben from deep geothermal boreholes, World Geothermal Congress, April 19 – 24 2015, Melbourne, Australia

Vidal J., Genter A., Schmittbuhl J. (2014). Evaluation of THC stimulations from acoustic image logs in the geothermal Rittershoffen well GRT-‐1 (France), European Geothermal Workshop, October 15 – 16 2014, KIT, Karlsruhe, Germany

Vidal J., Genter A., Duringer Ph., Manatschal G., Schmittbuhl J. (2013). Evidence of permeable fractures in the Triassic sediments of Northern Alsace, European Geothermal Workshop, October 24 – 25, EOST - University of Strasbourg 2013, France

Cuenot N., Scheiber J., Moeckes W., Guéry B., Bruzac S., Sontot O., Meneust P., Maquet J., Orsat J., Vidal J. (2013). Evolution of the natural radioactivity within the Soultz geothermal installation, European Geothermal Conference, June 3 – 7 2013, Pisa, Italy

Cuenot N., Goerke X., Guery B., Bruzac S., Sontot O., Meneust P., Maquet J., Vidal J. (2011). Evolution of the natural radioactivity within the Soultz geothermal installation, Soultz geothermal conference, October 5 – 6 2011, Soultz-sous-Forêts, France

  • Poster presentation

Vidal J., Genter A., Schmittbuhl J., Whitechurch H., Baujard C., Dalmais E. (2015). Evolution of concepts for the geothermal projects in the Upper Rhine Graben, European Geothermal Workshop, October 19 – 20 2015, EOST - University of Strasbourg, France

Girard-Berthet V., Vidal J., Whitechurch H., Ulrich M., Genter A., Schmittbuhl J. (2015). Hydrothermal alteration of Soultz-sous-Forêts granite near the granite-sediment interface in geothermal context, European Geothermal Workshop, October 19 – 20 2015, EOST - University of Strasbourg, France

Dalmais E., Genter A., Vidal J., Baujard C., Vuataz F.-D. (2015) Permeability assessment based on drilling data in EGS projects: Case study of Muschelkalk fracture in GRT-1 well for ECOGI Project (Rittershoffen, Alsace, France), European Geothermal Workshop, October 19 – 20 2015, EOST - University of Strasbourg, France 

Abstracts
  • Oral presentation

Vidal J., Genter A., Duringer Ph., Schmittbuhl J. (2014). Natural fracture permeability in Triassic sediments of the Upper Rhine Graben from deep geothermal boreholes, European Geosciences Union, 27 April – 2 May 2014, Wien, Austria

Cuenot N., Scheiber J., Moeckes W., Guéry B., Bruzac S., Sontot O., Meneust P., Maquet J., Orsat J., Vidal J. (2013). Radioprotection investigations during geothermal exploitation with Upper Rhine Valley fluids: power plant mapping and recommendations for future geothermal sites, Third European Geothermal Review, June 24 – 26 2013, Mainz, Germany

  • Poster presentation

Vidal J., Genter A., Schmittbuhl J., Baujard C. (2016). Hydraulic stimulation or low water injection in fractured reservoir of the geothermal well GRT-1 at Rittershoffen (France)?, American Geophysical Union Fall Meeting, December 12-16 2016, San Francisco, California, USA

Vidal J., Whitechurch H., Genter A., Schmittbuhl J., Baujard C. (2015). Permeability in fractured rocks from deep geothermal boreholes in the Upper Rhine Graben, European Geosciences Union, April 12-17 2015, Wien, Austria

Vidal J., Genter A., Duringer Ph., Aichholzer C., Schmittbuhl J. (2014). Permeable fractures in deep Triassic sediments of the Soultz geothermal wells (Alsace, France), Deep Geothermal Days, April 10 – 11 2014, Paris, France

Reports

Vidal J., (2014). Evaluation de l’impact des stimulations thermiques, chimiques et hydrauliques à partir de la caractérisation géologique et structurale du puits géothermique GRT-1 (Rittershoffen, France), Rapport confidentiel ESG, juin 2014, 66 pp.

Vidal J., (2014). Evaluation de l’impact des stimulations thermiques, chimiques et hydrauliques à partir de la caractérisation géologique et structurale du puits géothermique GRT-1 (Rittershoffen, France), Projet de Recherche – Master 2, Université de Strasbourg – EOST, mai 2014, 59 pp.

Vidal J., (2013). Banque de données du puits géothermique GRT-1, Rapport confidentiel ECOGI, juillet 2013, 44 pp.

Vidal J., (2013). Approche géologique et structurale multi-échelle de l'interface couverture-socle dans le fossé rhénan : application aux forages géothermiques de Soultz-sous-Forêts dans la partie sédimentaire, Projet de Recherche - Master 1, Université de Strasbourg – EOST, 25 pp.

Vidal J., et Vermorel S. (2012). Application of electric resistance tomography, ground-penetrating radar and magnetometry, Instituto de Geofsica, UNAM, Mexico D.F, août 2012, 13 pp.

Cuenot N., Bruzac S., Vidal J., (2010). Cartographie dosimétrique des installations géothermique, Rapport confidentiel GEIE Exploitation Minière de la Chaleur, RA03 003 2010 C juin 2010, 88 pp.