surfQuake: A New Python Toolbox for the Workflow Process of Seismic Sources Roberto Cabieces, Thiago C. Junqueira, Katrina Harris, Jesús Relinque, Claudio Satriano, et al. Seismological Research Letters, 2025 surfQuake is a new software designed to streamline the estimation of seismic source parameters. Its comprehensive set of toolboxes automates the determination of seismic arrival times, event association and locations, moment magnitude from P- or S-wave displacement spectra, and moment tensor inversions within a Bayesian framework. surfQuake is programmed in Python 3 and offers the users the possibility of three programming levels for flexibility and customization. The core library allows users to integrate the core of surfQuake into their preexisting scripts, giving advanced users full control, whereas the command-line interface gives users access to an upper layer that simplifies the use of the core. Alternatively, surfQuake core is wrapped by a graphical user interface and connected to an SQLite database, making it accessible to users with little coding experience. The software has been fully tested with an earthquake cluster of more than 2000 events that occurred in the central Pyrenees in 2021–2022. The source parameters retrieved from the cluster and the basic statistics associated with them are displayed using the surfQuake database toolbox. In addition, we offer a web tutorial with surfQuake documentation and a set of usage examples for the three programming levels.
A new automated procedure to obtain reliable moment tensor solutions of small to moderate earthquakes (3.0 ≤ M ≤ 5.5) in the Bayesian framework Yehezkiel Halauwet, Afnimar, Wahyu Triyoso, Jiří Vackář, Daryono Daryono, et al. Geophysical Journal International, 2024 SUMMARY The complete catalogue of moment tensor (MT) solutions is essential for a wide range of research in solid earth science. However, the number of reliable MT solutions for small to moderate earthquakes (3.0 ≤ M ≤ 5.5) is limited due to uncertainties arising from data and theoretical errors. In this study, we develop a new procedure to enhance the resolvability of MT solutions and provide more reliable uncertainty estimates for these smaller to moderate earthquakes. This procedure is fully automatic and efficiently accounts for both data and theoretical errors through two sets of hybrid linear–non-linear Bayesian inversions. In the inversion process, the covariance matrix is estimated using an empirical approach: the data covariance matrix is derived from the pre-event noise and the theoretical covariance matrix is derived from the residuals of the initial solution. We conducted tests using synthetic data generated from the 3-D velocity model and interference from background seismic noise. The tests found that using a combination of the non-Toeplitz data covariance matrix and the Toeplitz theoretical covariance matrix improves the solution and its uncertainties. Test results also suggest that including a theoretical covariance matrix when analysing MT in complex tectonic regions is essential, even if we have the best 1D velocity model. The application to earthquakes in the northern region of the Banda Arc resulted in the first published Regional Moment Tensor (RMT) catalogue, containing more than three times the number of trusted solutions compared to the Global Centroid Moment Tensor (GCMT) and the Indonesian Agency for Meteorology Climatology and Geophysics Moment Tensor (BMKG-MT) catalogue. The comparison shows that the trusted solutions align well with the focal mechanism of the GCMT and BMKG-MT, as well as with the maximum horizontal stress of the World Stress Map, and tectonic conditions in the study area. The newly obtained focal mechanisms provide several key findings: (i) they confirm that the deformation in the northern and eastern parts of Seram Island is influenced by oblique intraplate convergence rather than by the subduction process; (ii) they validate the newly identified Amahai Fault with a greater number of focal mechanisms and (iii) they reveal an earthquake Mw 4.7 with the same location and source mechanism 6 yr before the 2019 Ambon-Kairatu earthquake (Mw 6.5) which occurred on a previously unidentified fault.
Dependence of the Electronic Structure of β-Si6−zAlzOzN8−z on the (Al,O) Concentration z and on the Temperature Saleem Ayaz Khan, Ondřej Šipr, Jiří Vackář, Ján Minár Zeitschrift Fur Anorganische Und Allgemeine Chemie, 2022 β‐Si6−zAlzOzN8−z is a prominent example of systems suitable as hosts for creating materials for light‐emitting diodes (LEDs). In this work, the electronic structure of a series of semiordered and disordered β‐Si6−zAlzOzN8−z systems is investigated by means of ab initio calculations, using the FLAPW and Green function KKR methods. Finite temperature effects are included by averaging over thermodynamic configurations within the alloy analogy model. We found that the dependence of the electronic structure on the (Al,O) concentration z is similar for semiordered and disordered structures. The electronic band gap decreases with increasing z by about 1.5 eV when going from z=0 to z=2. States at the top of the valence band are mostly associated with N atoms whereas the states at the bottom of the conduction band are mostly derived from O atoms. Increasing the temperature leads to a shift of the bottom of the conduction band to lower energies. The amount of this shift increases with increasing z.
Temperature-induced changes in the magnetism of Laves phase rare-earth-iron intermetallics by ab initio calculations O. Šipr, S. Mankovsky, J. Vackář, H. Ebert, A. Marmodoro Physical Review B, 2022 Laves RFe 2 compounds, where R is a rare earth, exhibit technologically relevant properties associated with the interplay between their lattice geometry and magnetism. We apply ab initio calculations to explore how magnetic properties of Fe in RFe 2 systems vary with temperature. We found that the ratio between the orbital magnetic moment µ orb and the spin magnetic moment µ spin increases with increasing temperature for YFe 2 , GdFe 2 , TbFe 2 , DyFe 2 , and HoFe 2 . This increase is significant and it should be experimentally observable by means of x-ray magnetic circular dichroism. We conjecture that the predicted increase of the µ orb /µ spin ratio with temperature is linked to the reduction of hybridization between same-spin-channel states of atoms with fluctuating magnetic moments and to the associated increase of their atomic-like character.
Finite element code in Python as a universal and modular tool applied to Kohn-Sham equations Eccomas 2012 European Congress on Computational Methods in Applied Sciences and Engineering E Book Full Papers, 2012
Connection between spectral features of B K edge XANES of minerals and the local structure Physics and Chemistry of Glasses European Journal of Glass Science and Technology Part B, 2006
Electronic structure and x-ray bands Antonín Šimůnek, Jiří Vackář, Martin Polčík, Jiří Drahokoupil, Walter Wolf, et al. Physical Review B Condensed Matter and Materials Physics, 2000
