The Alpine mountains are known for a complex tectonic history. We shed light onto ongoing tectonic processes by studying rupture mechanisms of small to moderate earthquakes between 2016 and 2019 observed by the temporary AlpArray seismic network. The rupture processes of 75 earthquakes were analyzed, along with past earthquakes and deformation data. Our observations point at variations in the underlying tectonic processes and stress regimes across the Alps.

Generating an accurate model of the subsurface is crucial when assessing a site for CO₂ storage, particularly for a fault-bound storage site that may act as a seal or could reactivate upon CO₂ injection. However, we have shown how picking strategy, i.e. line spacing, chosen to create the model significantly influences any subsequent fault analyses but is surprisingly rarely discussed. This analysis has been performed on the Vette Fault bounding the Smeaheia potential CO₂ storage site.

The influence and interaction of elastic material properties (Young's modulus, Poisson's ratio), density and low-friction faults on the resulting far-field stress pattern in the Earth's crust is tested with generic models. A Young's modulus contrast can lead to a significant stress rotation. Discontinuities with low friction in homogeneous models change the stress pattern only slightly, away from the fault. In addition, active discontinuities are able to compensate stress rotation.

Balancing along geological cross sections reveals that the Giudicarie Belt comprises two kinematic domains. The SW domain accommodated at least ~ 18 km Late Oligocene to Early Miocene shortening. Since the Middle Miocene, the SW domain experienced at least ~ 12–22 km shortening, whereas the NE domain underwent at least ~ 25–35 km. Together, these domains contributed to ~ 40–47 km of sinistral offset of the Periadriatic Fault along the Northern Giudicarie Fault since the Late Oligocene.

Constraining the conditions at which rocks form is crucial for understanding geologic processes. For years, the conditions under which rocks from Syros, Greece, formed have remained enigmatic; yet these rocks are fundamental for understanding processes occurring at the interface between colliding tectonic plates (subduction zones). Here, we constrain conditions under which these rocks formed and show they were transported to the surface adjacent to the down-going (subducting) tectonic plate.

Although viscosity of the crust largely exceeds that of magmas, we show, based on the Aegean and Tyrrhenian Miocene syn-kinematic plutons, how the intrusion of granites in extensional contexts is controlled by crustal deformation, from magmatic stage to cold mylonites. We show that a simple numerical setup with partial melting in the lower crust in an extensional context leads to the formation of metamorphic core complexes and low-angle detachments reproducing the observed evolution of plutons.

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.

Mexican seismic stations witnessed a reduction in noise level as a result of the COVID-19 lockdown strategies. The largest drop was observed in Hermosillo, which is also the city with the fastest noise-level recovery and a quick increase in confirmed COVID-19 cases. Since 1 June 2020, a traffic-light system has modulated the re-opening of economic activities for each state, which is reflected in noise levels. Noise reduction has allowed the identification and perception of smaller earthquakes.

The increasing use of distributed acoustic sensing (DAS) inhibits the transformation of optical fibers into dense arrays of seismo-acoustic sensors. Here, DAS strain records are converted to ground motions using the waves' apparent velocity. An algorithm for velocity determination is presented, accounting for velocity variations between different seismic waves. The conversion allows for robust determination of fundamental source parameters, earthquake magnitude and stress drop.

Basin inversion in central Europe is believed to have started during Late Cretaceous (middle Turonian) and probably proceeded until the Paleogene. Data from different marginal troughs in central Europe point to an earlier start of basin inversion (in the Cenomanian). The end of inversion is overprinted by general uplift but had probably already occurred in the late Campanian to Maastrichtian. Both the start and end of inversion occurred with low rates of uplift and subsidence.