Articles | Volume 12, issue 3
https://doi.org/10.5194/se-12-581-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/se-12-581-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
04 Mar 2021
Research article |
| 04 Mar 2021
| 04 Mar 2021
Seismicity during and after stimulation of a 6.1 km deep enhanced geothermal system in Helsinki, Finland
Maria Leonhardt
CORRESPONDING AUTHOR
Helmholtz Centre Potsdam, GFZ German Research Centre for Geosciences,
Sect. 4.2: Geomechanics and Scientific Drilling, Potsdam, Germany
Grzegorz Kwiatek
Helmholtz Centre Potsdam, GFZ German Research Centre for Geosciences,
Sect. 4.2: Geomechanics and Scientific Drilling, Potsdam, Germany
Patricia Martínez-Garzón
Helmholtz Centre Potsdam, GFZ German Research Centre for Geosciences,
Sect. 4.2: Geomechanics and Scientific Drilling, Potsdam, Germany
Marco Bohnhoff
Helmholtz Centre Potsdam, GFZ German Research Centre for Geosciences,
Sect. 4.2: Geomechanics and Scientific Drilling, Potsdam, Germany
Department of Earth Sciences, Free University of Berlin, Berlin,
Germany
Tero Saarno
St1 Deep Heat Oy, Helsinki, Finland
Pekka Heikkinen
St1 Deep Heat Oy, Helsinki, Finland
Department of
Geosciences and Geography, University of Helsinki, Helsinki, Finland
Georg Dresen
Helmholtz Centre Potsdam, GFZ German Research Centre for Geosciences,
Sect. 4.2: Geomechanics and Scientific Drilling, Potsdam, Germany
Institute of Earth and Environmental Sciences, University of Potsdam,
Potsdam, Germany
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Lauro Chiaraluce, Richard Bennett, David Mencin, Wade Johnson, Massimiliano Rinaldo Barchi, Marco Bohnhoff, Paola Baccheschi, Antonio Caracausi, Carlo Calamita, Adriano Cavaliere, Adriano Gualandi, Eugenio Mandler, Maria Teresa Mariucci, Leonardo Martelli, Simone Marzorati, Paola Montone, Debora Pantaleo, Stefano Pucci, Enrico Serpelloni, Mariano Supino, Salvatore Stramondo, Catherine Hanagan, Liz Van Boskirk, Mike Gottlieb, Glen Mattioli, Marco Urbani, Francesco Mirabella, Assel Akimbekova, Simona Pierdominici, Thomas Wiersberg, Chris Marone, Luca Palmieri, and Luca Schenato
Sci. Dril., 33, 173–190, https://doi.org/10.5194/sd-33-173-2024, https://doi.org/10.5194/sd-33-173-2024, 2024
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We built six observatory stations in central Italy to monitor a fault potentially capable of generating a strong earthquake. Each site has 80–160 m deep wells equipped with strainmeters and seismometers. At the surface, we placed GNSS antennas and seismic and meteorological sensors. All data, which are open access for the scientific community, will help us to better understand the complex physical and chemical processes that lead to the generation of the full range of slow and fast earthquakes.
Patricia Martínez-Garzón, Dirk Becker, Jorge Jara, Xiang Chen, Grzegorz Kwiatek, and Marco Bohnhoff
Solid Earth, 14, 1103–1121, https://doi.org/10.5194/se-14-1103-2023, https://doi.org/10.5194/se-14-1103-2023, 2023
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We analyze the 2022 MW 6.0 Gölyaka sequence. A high-resolution seismicity catalog revealed no spatiotemporal localization and lack of immediate foreshocks. Aftershock distribution suggests the activation of the Karadere and Düzce faults. The preferential energy propagation suggests that the mainshock propagated eastwards, which is in agreement with predictions from models, where the velocity in the two sides of the fault is different.
Audrey Bonnelye, Pierre Dick, Marco Bohnhoff, Fabrice Cotton, Rüdiger Giese, Jan Henninges, Damien Jougnot, Grzegorz Kwiatek, and Stefan Lüth
Adv. Geosci., 58, 177–188, https://doi.org/10.5194/adgeo-58-177-2023, https://doi.org/10.5194/adgeo-58-177-2023, 2023
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The overall objective of the CHENILLE project is to performed an in-situ experiment in the Underground Reaserch Laboratory of Tournemire (Southern France) consisting of hydraulic and thermal stimulation of a fault zone. This experiment is monitored with extensive geophysical means (passive seismic, active seismic, distributed fiber optics for temperature measurements) in order to unravel the physical processes taking place during the stimulation for a better charactization of fault zones.
Carolin M. Boese, Grzegorz Kwiatek, Thomas Fischer, Katrin Plenkers, Juliane Starke, Felix Blümle, Christoph Janssen, and Georg Dresen
Solid Earth, 13, 323–346, https://doi.org/10.5194/se-13-323-2022, https://doi.org/10.5194/se-13-323-2022, 2022
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Hydraulic stimulation experiments in underground facilities allow for placing monitoring equipment close to and surrounding the stimulated rock under realistic and complex conditions at depth. We evaluate how accurately the direction-dependent velocity must be known for high-resolution seismic monitoring during stimulation. Induced transient deformation in rocks only 2.5–5 m apart may differ significantly in magnitude and style, and monitoring requires sensitive sensors adapted to the frequency.
Related subject area
Subject area: Tectonic plate interactions, magma genesis, and lithosphere deformation at all scales | Editorial team: Seismics, seismology, paleoseismology, geoelectrics, and electromagnetics | Discipline: Seismology
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Seismicity and seismotectonics of the Albstadt Shear Zone in the northern Alpine foreland
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Rupture-dependent breakdown energy in fault models with thermo-hydro-mechanical processes
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Moment magnitude estimates for central Anatolian earthquakes using coda waves
Event couple spectral ratio Q method for earthquake clusters: application to northwest Bohemia
Berkan Özkan, Tuna Eken, Peter Gaebler, and Tuncay Taymaz
EGUsphere, https://doi.org/10.5194/egusphere-2024-721, https://doi.org/10.5194/egusphere-2024-721, 2024
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This study estimates source properties by analyzing seismic data of 303 earthquakes (2018–2020) in Marmara Region, Turkey and finds a strong correlation between Mw-coda and ML. Moreover, the scaled energy increases with seismic moment estimates and shows non-self similar scaling in earthquake sources.
Quetzalcoatl Rodríguez-Pérez and F. Ramón Zúñiga
Solid Earth, 15, 229–249, https://doi.org/10.5194/se-15-229-2024, https://doi.org/10.5194/se-15-229-2024, 2024
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The behavior of seismic energy parameters and their possible dependence on the type of fault for globally detected earthquakes were studied. For this purpose, different energy estimation methods were used. Equations were obtained to convert energies obtained in different ways. The dependence of the seismic energy on the focal mechanism was confirmed up to depths close to 180 km. The results will help to explain the seismic rupture of earthquakes generated at greater depth.
Patricia Martínez-Garzón, Dirk Becker, Jorge Jara, Xiang Chen, Grzegorz Kwiatek, and Marco Bohnhoff
Solid Earth, 14, 1103–1121, https://doi.org/10.5194/se-14-1103-2023, https://doi.org/10.5194/se-14-1103-2023, 2023
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We analyze the 2022 MW 6.0 Gölyaka sequence. A high-resolution seismicity catalog revealed no spatiotemporal localization and lack of immediate foreshocks. Aftershock distribution suggests the activation of the Karadere and Düzce faults. The preferential energy propagation suggests that the mainshock propagated eastwards, which is in agreement with predictions from models, where the velocity in the two sides of the fault is different.
Laurens Jan Hofman, Jörn Kummerow, Simone Cesca, and the AlpArray–Swath-D Working Group
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We present an earthquake catalogue for the eastern and southern Alps based on data from a local temporary monitoring network. The methods we developed for the detection and localisation focus especially on very small earthquakes. This provides insight into the local geology and tectonics and provides an important base for future research in this part of the Alps.
Jaroslava Plomerová, Helena Žlebčíková, György Hetényi, Luděk Vecsey, Vladislav Babuška, and AlpArray-EASI and AlpArray working
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Solid Earth, 13, 251–270, https://doi.org/10.5194/se-13-251-2022, https://doi.org/10.5194/se-13-251-2022, 2022
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We present high-resolution tomography images of upper mantle structure beneath the E Alps and the adjacent Bohemian Massif. The northward-dipping lithosphere, imaged down to ∼200 km beneath the E Alps without signs of delamination, is probably formed by a mixture of a fragment of detached European plate and the Adriatic plate subductions. A detached high-velocity anomaly, sub-parallel to and distinct from the E Alps heterogeneity, is imaged at ∼100–200 km beneath the southern part of the BM.
Martin Thorwart, Anke Dannowski, Ingo Grevemeyer, Dietrich Lange, Heidrun Kopp, Florian Petersen, Wayne C. Crawford, Anne Paul, and the AlpArray Working Group
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We analyse broadband ocean bottom seismometer data of the AlpArray OBS network in the Ligurian Basin. Two earthquake clusters with thrust faulting focal mechanisms indicate compression of the rift basin. The locations of seismicity suggest reactivation of pre-existing rift structures and strengthening of crust and uppermost mantle during rifting-related extension. Slightly different striking directions of faults may mimic the anti-clockwise rotation of the Corsica–Sardinia block.
Rainer Kind, Stefan M. Schmid, Xiaohui Yuan, Benjamin Heit, Thomas Meier, and the AlpArray and AlpArray-SWATH-D Working Groups
Solid Earth, 12, 2503–2521, https://doi.org/10.5194/se-12-2503-2021, https://doi.org/10.5194/se-12-2503-2021, 2021
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A large amount of new seismic data from the greater Alpine area have been obtained within the AlpArray and SWATH-D projects. S-to-P converted seismic phases from the Moho and from the mantle lithosphere have been processed with a newly developed method. Examples of new observations are a rapid change in Moho depth at 13° E below the Tauern Window from 60 km in the west to 40 km in the east and a second Moho trough along the boundary of the Bohemian Massif towards the Western Carpathians.
Mario Arroyo-Solórzano, Diego Castro-Rojas, Frédérick Massin, Lepolt Linkimer, Ivonne Arroyo, and Robin Yani
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We present the first seismic noise variation levels during COVID-19 in Central America using 10 seismometers. We study the impact of the seismic noise reduction on the detectability of earthquakes and on the felt reports. Our results show maximum values (~50 % decrease) at seismic stations near airports and densely inhabited cities. The decrease in seismic noise improved earthquake locations and reports. Seismic noise could also be useful to verify compliance with lockdown measures.
Marguerite Mathey, Christian Sue, Colin Pagani, Stéphane Baize, Andrea Walpersdorf, Thomas Bodin, Laurent Husson, Estelle Hannouz, and Bertrand Potin
Solid Earth, 12, 1661–1681, https://doi.org/10.5194/se-12-1661-2021, https://doi.org/10.5194/se-12-1661-2021, 2021
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This work features the highest-resolution seismic stress and strain fields available at the present time for the analysis of the active crustal deformation of the Western Alps. In this paper, we address a large dataset of newly computed focal mechanisms from a statistical standpoint, which allows us to suggest a joint control from far-field forces and from buoyancy forces on the present-day deformation of the Western Alps.
Sarah Mader, Joachim R. R. Ritter, Klaus Reicherter, and the AlpArray Working Group
Solid Earth, 12, 1389–1409, https://doi.org/10.5194/se-12-1389-2021, https://doi.org/10.5194/se-12-1389-2021, 2021
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The Albstadt Shear Zone, SW Germany, is an active rupture zone with sometimes damaging earthquakes but no visible surface structure. To identify its segmentations, geometry, faulting pattern and extension, we analyze the continuous earthquake activity in 2011–2018. We find a segmented N–S-oriented fault zone with mainly horizontal and minor vertical movement along mostly NNE- and some NNW-oriented rupture planes. The main horizontal stress is oriented NW and due to Alpine-related loading.
Manvendra Singh and Georg Rümpker
Solid Earth, 11, 2557–2568, https://doi.org/10.5194/se-11-2557-2020, https://doi.org/10.5194/se-11-2557-2020, 2020
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Using seismic array methods, 63 events were located in the Rodrigues–CIR region, not reported by any global network, most of them being off the ridge axis. The lack of seismicity along this section of the CIR, as observed from global data and this study, can possibly be attributed to the presence of partially molten mantle beneath Rodrigues Ridge. The results will be of interest for a broad range of geoscientists interested in the tectonic evolution of Indian Ocean and plume–crust interaction.
Valère Lambert and Nadia Lapusta
Solid Earth, 11, 2283–2302, https://doi.org/10.5194/se-11-2283-2020, https://doi.org/10.5194/se-11-2283-2020, 2020
Dominik Zbinden, Antonio Pio Rinaldi, Tobias Diehl, and Stefan Wiemer
Solid Earth, 11, 909–933, https://doi.org/10.5194/se-11-909-2020, https://doi.org/10.5194/se-11-909-2020, 2020
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The deep geothermal project in St. Gallen, Switzerland, aimed at generating electricity and heat. The fluid pumped into the underground caused hundreds of small earthquakes and one larger one felt by the local population. Here we use computer simulations to study the physical processes that led to the earthquakes. We find that gas present in the subsurface could have intensified the seismicity, which may have implications for future geothermal projects conducted in similar geological conditions.
Quetzalcoatl Rodríguez-Pérez, Víctor Hugo Márquez-Ramírez, and Francisco Ramón Zúñiga
Solid Earth, 11, 791–806, https://doi.org/10.5194/se-11-791-2020, https://doi.org/10.5194/se-11-791-2020, 2020
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We analyzed reported oceanic earthquakes in Mexico. We used data from different agencies. By analyzing the occurrence of earthquakes, we can extract relevant information such as the level of seismic activity, the size of the earthquakes, hypocenter depths, etc. We also studied the focal mechanisms to classify the different types of earthquakes and calculated the stress in the region. The results will be useful to understand the physics of oceanic earthquakes.
Nienke Blom, Alexey Gokhberg, and Andreas Fichtner
Solid Earth, 11, 669–690, https://doi.org/10.5194/se-11-669-2020, https://doi.org/10.5194/se-11-669-2020, 2020
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We have developed a model of the Earth's structure in the upper 500 km beneath the central and eastern Mediterranean. Within this model, we can see parts of the African tectonic plate that have sunk underneath the European plate over the past tens of millions of years. This model was constructed using seismic waveform tomography by matching the seismograms from many earthquakes recorded at the surface to synthetic seismograms that were generated by simulating earthquake wave propagation.
Linus Villiger, Valentin Samuel Gischig, Joseph Doetsch, Hannes Krietsch, Nathan Oliver Dutler, Mohammadreza Jalali, Benoît Valley, Paul Antony Selvadurai, Arnaud Mignan, Katrin Plenkers, Domenico Giardini, Florian Amann, and Stefan Wiemer
Solid Earth, 11, 627–655, https://doi.org/10.5194/se-11-627-2020, https://doi.org/10.5194/se-11-627-2020, 2020
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Hydraulic stimulation summarizes fracture initiation and reactivation due to high-pressure fluid injection. Several borehole intervals covering intact rock and pre-existing fractures were targets for high-pressure fluid injections within a decameter-scale, crystalline rock volume. The observed induced seismicity strongly depends on the target geology. In addition, the severity of the induced seismicity per experiment counter correlates with the observed transmissivity enhancement.
Gaelle Lamarque and Jordi Julià
Solid Earth, 10, 893–905, https://doi.org/10.5194/se-10-893-2019, https://doi.org/10.5194/se-10-893-2019, 2019
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Our goal is to better understand the evolution of the Earth's outer shell in northeast Brazil. We analyze the propagation properties (anisotropy) of distant seismic waves in order to look for subsurface, large-scale deformation structures. Results show that structures visible at the surface can be traced down to ~100 km depth, that the imprint of the opening of the Atlantic Ocean can be detected along the coast and that the continental interior is anomalous due to a complex deformation history.
Víctor Vilarrasa, Jesus Carrera, Sebastià Olivella, Jonny Rutqvist, and Lyesse Laloui
Solid Earth, 10, 871–892, https://doi.org/10.5194/se-10-871-2019, https://doi.org/10.5194/se-10-871-2019, 2019
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To meet the goal of the Paris Agreement to limit temperature increase below 2 ºC, geologic carbon storage (GCS) will be necessary at the gigatonne scale. But to successfully deploy GCS, seismicity induced by CO2 injection should be controlled and maintained below a threshold that does not generate nuisances to the population. We conclude that felt induced seismicity can be minimized provided that a proper site characterization, monitoring and pressure management are performed.
Tuna Eken
Solid Earth, 10, 713–723, https://doi.org/10.5194/se-10-713-2019, https://doi.org/10.5194/se-10-713-2019, 2019
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Proper magnitude estimates for earthquakes can give insight into the seismic energy released at an earthquake source. This is, in fact, essential for better seismic hazard assessments in tectonically active regions. In the present work, I examine local earthquakes in central Anatolia to estimate their moment magnitudes. The main outcome of this study is an empirical relation that can provide a direct physical quantity of seismic energy in the study region.
Marius Kriegerowski, Simone Cesca, Matthias Ohrnberger, Torsten Dahm, and Frank Krüger
Solid Earth, 10, 317–328, https://doi.org/10.5194/se-10-317-2019, https://doi.org/10.5194/se-10-317-2019, 2019
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We developed a method that allows to estimate the acoustic attenuation of seismic waves within regions with high earthquake source densities. Attenuation is of high interest as it allows to draw conclusions on the origin of seismic activity. We apply our method to north-west Bohemia, which is regularly affected by earthquake swarms during which thousands of earthquakes are registered within a few days. We find reduced attenuation within the active volume, which may indicate high fluid content.
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