Updated stress dataset of the Circum-Pannonian region: Implications for regional tectonics and geo-energy applications

• Published in: Tectonophysics Vol. 856; p. 229860
• Main Authors: Békési, Eszter, Porkoláb, Kristóf, Wesztergom, Viktor, Wéber, Zoltán
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 05.06.2023
• Subjects: Active tectonics; Earthquake focal mechanism; Pannonian basin; Stress field; Active tectonics; Pannonian basin; Stress field; Earthquake focal mechanism
• ISSN: 0040-1951; 1879-3266
• DOI: 10.1016/j.tecto.2023.229860

In this paper we present the updated stress database of the Circum-Pannonian region in Central-Eastern Europe, containing stress indicators from earthquake focal mechanism solutions, borehole breakout analysis, overcoring measurements and geologic fault-slip data. Recent improvements in seismic network density in the framework of the AlpArray project, as well as methodological advancements, facilitated the calculation of focal mechanism solutions of small magnitude events, contributing to the more detailed reconstruction of the stress field in the area. The new database consists of 368 A – C quality stress indicators that we interpolate to a regular grid to produce stress orientation and relative stress magnitude maps. Interpolated maximum horizontal stress (SH) orientations are in general marked by low uncertainties (mostly between 10° – 30°), indicating that the interpolation results can be considered reliable for the majority of the study area. Inferred SH directions show a good fit with previous studies, confirming earlier findings that the Pannonian basin is under compression and transpression, controlled by the combination of its landlocked position with the N-NE directed motion of the Adriatic microplate. The new tectonic regime map highlights several new features, such as the complete absence of extension in the entire Pannonian basin. The determined stress regimes and trajectories calculated from interpolated SH directions generally agree well with the orientation and kinematics of neotectonic structures in the Pannonian region. Additionally, measured and interpolated SH directions and faulting styles can provide boundary conditions for geomechanical studies, serving as valuable input for geo-energy applications. •A new stress database of the Circum-Pannonian region and its detailed analysis is presented.•Focal mechanism solutions of small (M < 4) magnitude events are resolved, utilizing the AlpArray seismic network.•The new tectonic regime map shows the complete absence of extension in the entire Pannonian basin.•The results are discussed in the context of active deformation and geo-energy applications.