eprintid: 2449 rev_number: 10 eprint_status: archive userid: 6 dir: disk0/00/00/24/49 datestamp: 2024-07-16 07:35:14 lastmod: 2024-07-16 07:35:14 status_changed: 2024-07-16 07:35:14 type: article metadata_visibility: show creators_name: Wang, Lei creators_name: Kwiatek, Grzegorz creators_name: Renard, François creators_name: Guérin-Marthe, Simon creators_name: Rybacki, Erik creators_name: Bohnhoff, Marco creators_name: Naumann, Michael creators_name: Dresen, Georg corp_creators: Helmholtz Centre Potsdam, GFZ German Research Centre for Geosciences, Geomechanics and Scientific Drilling, Potsdam 14473, Germany corp_creators: Helmholtz Centre Potsdam, GFZ German Research Centre for Geosciences, Geomechanics and Scientific Drilling, Potsdam 14473, Germany corp_creators: The Njord Centre, Department of Geosciences, University of Oslo, Oslo 0316, Norway The Njord Centre, Department of Physics, University of Oslo, Oslo 0316, Norway ISTerre, Université Grenoble Alpes, Grenoble INP, Université Savoie Mont Blanc, CNRS, IRD, Un corp_creators: Helmholtz Centre Potsdam, GFZ German Research Centre for Geosciences, Geomechanics and Scientific Drilling, Potsdam 14473, Germany Laboratory of Experimental Rock Mechanics, Civil Engineering Institute, École Polytechnique Fédérale de Lausanne, Lausanne 1 corp_creators: Helmholtz Centre Potsdam, GFZ German Research Centre for Geosciences, Geomechanics and Scientific Drilling, Potsdam 14473, Germany corp_creators: Helmholtz Centre Potsdam, GFZ German Research Centre for Geosciences, Geomechanics and Scientific Drilling, Potsdam 14473, Germany Department of Earth Sciences, Free University Berlin, Berlin 12249, Germany corp_creators: Helmholtz Centre Potsdam, GFZ German Research Centre for Geosciences, Geomechanics and Scientific Drilling, Potsdam 14473, Germany corp_creators: Helmholtz Centre Potsdam, GFZ German Research Centre for Geosciences, Geomechanics and Scientific Drilling, Potsdam 14473, Germany Institute of Earth and Environmental Science, University of Potsdam, Potsdam 14469, Germany title: Fault roughness controls injection-induced seismicity subjects: LX subjects: RG divisions: GEO4 full_text_status: none abstract: Surface roughness ubiquitously prevails in natural faults across various length scales. Despite extensive studies highlighting the important role of fault geometry in the dynamics of tectonic earthquakes, whether and how fault roughness affects fluid-induced seismicity remains elusive. Here, we investigate the effects of fault geometry and stress heterogeneity on fluid-induced fault slip and associated seismicity characteristics using laboratory experiments and numerical modeling. We perform fluid injection experiments on quartz-rich sandstone samples containing either a smooth or a rough fault. We find that geometrical roughness slows down injection-induced fault slip and reduces macroscopic slip velocities and fault slip-weakening rates. Stress heterogeneity and roughness control hypocenter distribution, frequency–magnitude characteristics, and source mechanisms of injection-induced acoustic emissions (AEs) (analogous to natural seismicity). In contrast to smooth faults where injection-induced AEs are uniformly distributed, slip on rough faults produces spatially localized AEs with pronounced non-double-couple source mechanisms. We demonstrate that these clustered AEs occur around highly stressed asperities where induced local slip rates are higher, accompanied by lower Gutenberg–Richter b-values. Our findings suggest that real-time monitoring of induced microseismicity during fluid injection may allow identifying progressive localization of seismic activity and improve forecasting of runaway events. date: 2024 publication: Proceedings of the National Academy of Sciences volume: 121 number: 3 id_number: doi:10.1073/pnas.2310039121 issn: 0027-8424 official_url: https://doi.org/10.1073/pnas.2310039121 access_IS-EPOS: limited owner: Publisher citation: Wang, Lei and Kwiatek, Grzegorz and Renard, François and Guérin-Marthe, Simon and Rybacki, Erik and Bohnhoff, Marco and Naumann, Michael and Dresen, Georg (2024) Fault roughness controls injection-induced seismicity. Proceedings of the National Academy of Sciences, 121 (3). DOI: https://doi.org/10.1073/pnas.2310039121