error
Kurzer Serviceunterbruch am Donnerstag, 3. März 2026, 12 bis 13 Uhr. Sie können in diesem Zeitraum keine neuen Dokumente hochladen oder bestehende Einträge bearbeiten. Das Login wird in diesem Zeitraum deaktiviert. Grund: Wartungsarbeiten // Short service interruption on Thursday, March 3, 2026, 12.00 – 13.00. During this time, you won’t be able to upload new documents or edit existing records. The login will be deactivated during this time. Reason: maintenance work
 

Toni Kraft


Last Name

Kraft

First Name

Toni

ORCID

0000-0002-9157-8953

Organisational unit

02818 - Schweiz. Erdbebendienst (SED) / Swiss Seismological Service (SED)

Filters

Reset filters

Search Results

Publications 1 - 10 of 48
  • Analysis of induced microseismicity at the geothermal project Schlattingen (Canton Thurgau, Switzerland)
    Item type: Report
    Kraft, Toni; Herrmann, Marcus; Diehl, Tobias (2016)
    Nagra Project Report
  • Earthquakes in Switzerland and surrounding regions during 2013
    Item type: Journal Article
    Diehl, Tobias; Clinton, John Francis; Kraft, Toni; et al. (2014)
    Swiss Journal of Geosciences
    This report of the Swiss Seismological Service summarizes the seismic activity in Switzerland and surrounding regions during 2013. During this period, 699 earthquakes and 208 quarry blasts were detected and located in the region under consideration. With a total of 18 events with local magnitudes ML ≥ 2.5, the seismic activity in the year 2013 was slightly below the average over the previous 38 years. Most noteworthy were the two earthquake sequences of St. Gallen (SG) in July and Balzers (FL) in December. The former was induced by reservoir stimulation operations at the St. Gallen geothermal project. The maximum local magnitude in the sequence was 3.5, comparable in size with the ML 3.4 event induced by stimulation operations below Basel in 2006. The sequence of Balzers was associated with an ML 4.1 earthquake in the border region to Liechtenstein. More than 30 aftershocks with magnitudes ranging between ML −0.2 and ML 3.7 were detected in the month following the mainshock. The ML 3.5 St. Gallen and the ML 4.1 Balzers earthquakes were widely felt by the public but no reports on damages are known. The maximum intensity for both events was IV.
  • Abschlussbericht Projekt – GEOBEST
    Item type: Other Publication
    Kraft, Toni; Wiemer, Stefan (2015)
  • Induzierte Erdbeben im Nachgang des eingestellten Geothermieprojekts in Basel
    Item type: Report
    Wiemer, Stefan; Tormann, Thessa; Herrmann, Marcus; et al. (2017)
  • The induced earthquake sequence related to the St. Gallen deep geothermal project (Switzerland): Fault reactivation and fluid interactions imaged by microseismicity
    Item type: Journal Article
    Diehl, Tobias; Kraft, Toni; Kissling, Eduard; et al. (2017)
    Journal of Geophysical Research: Solid Earth
    In July 2013, a sequence of more than 340 earthquakes was induced by reservoir stimulations and well-control procedures following a gas kick at a deep geothermal drilling project close to the city of St. Gallen, Switzerland. The sequence culminated in an ML 3.5 earthquake, which was felt within 10–15 km from the epicenter. High-quality earthquake locations and 3-D reflection seismic data acquired in the St. Gallen project provide a unique data set, which allows high-resolution studies of earthquake triggering related to the injection of fluids into macroscopic fault zones. In this study, we present a high-precision earthquake catalog of the induced sequence. Absolute locations are constrained by a coupled hypocenter-velocity inversion, and subsequent double-difference relocations image the geometry of the ML 3.5 rupture and resolve the spatiotemporal evolution of seismicity. A joint interpretation of earthquake and seismic data shows that the majority of the seismicity occurred in the pre-Mesozoic basement, hundreds of meters below the borehole and the targeted Mesozoic sequence. We propose a hydraulic connectivity between the reactivated fault and the borehole, likely through faults mapped by seismic data. Despite the excellent quality of the seismic data, the association of seismicity with mapped faults remains ambiguous. In summary, our results document that the actual hydraulic properties of a fault system and hydraulic connections between its fault segments are complex and may not be predictable upfront. Incomplete knowledge of fault structures and stress heterogeneities within highly complex fault systems additionally challenge the degree of predictability of induced seismicity related to underground fluid injections.
  • Optimization of a large-scale microseismic monitoring network in northern Switzerland
    Item type: Journal Article
    Kraft, Toni; Mignan, Arnaud; Giardini, Domenico (2013)
    Geophysical Journal International
  • A Consistent High-Resolution Catalog of Induced Seismicity in Basel Based on Matched Filter Detection and Tailored Post-Processing
    Item type: Journal Article
    Herrmann, Marcus; Kraft, Toni; Tormann, Thessa; et al. (2019)
    Journal of Geophysical Research: Solid Earth
    Seismic monitoring of the Basel Enhanced Geothermal System (EGS) has been running for more than a decade. Yet, the details of the long-term behavior of its induced seismicity remained unexplored because a seismic event catalog with consistent detection sensitivity and magnitudes did not exist. This knowledge is essential for developing guidelines and mitigation procedures on how to safely operate and terminate injection activities. Only few observational data exist that cover all phases of such projects in a consistent manner. Here, we describe a method that overcomes these deficiencies based on sensitive matched filter detection and a machine learning approach to remove false detections. With an emphasis on consistency, we create a catalog that contains more than 280 000 events down to Mw−1.5. The much higher temporal resolution allows us to analyze induced microearthquakes in great detail and to gain new insights. We resolved temporal variations of seismicity parameters and, in the post-operational phase, a preferential temporal clustering of events. We find a breakdown in the Gutenberg--Richter scaling during reservoir stimulation, which may have physical reasons or could be caused by a method-independent detection limit during high event rates. The scaling breakdown has implications for the design of Adaptive Traffic Light Systems and may limit the potential of real-time mitigation strategies in future EGS projects. Nevertheless, our catalog gives the opportunity to study the temporal evolution of the sequence in unprecedented detail, which will help to better understand the physical processes in a geothermal reservoir, potentially not only in the Basel case.
  • Longterm decay and possible reactivation of induced seismicity at the Basel EGS site
    Item type: Conference Poster
    Herrmann, Marcus; Kraft, Toni; Tormann, Thessa; et al. (2016)
  • Modeling detection thresholds of microseismic monitoring networks
    Item type: Other Conference Item
    Goertz, Alexander; Riahi, Nima; Kraft, Toni; et al. (2012)
    SEG Technical Program Expanded Abstracts 2012
  • High-precision relocation of induced seismicity in the geothermal system below St. Gallen (Switzerland)
    Item type: Other Conference Item
    Diehl, Tobias; Kraft, Toni; Kissling, Eduard; et al. (2014)
    Jahrestagung der Deutschen Geophysikalischen Gesellschaft ~ Tagungsband der 74. Jahrestagung der Deutschen Geophysikalischen Gesellschaft
Publications 1 - 10 of 48