Foreshocks are among the most powerful tools to study the processes that occur before main earthquakes. However, their detection is still sparse, especially for relatively small earthquakes. We present here a detailed foreshock analysis for the 2019 Balsorano (Italy) earthquake (Mw4.4). To improve the detection before and after the mainshock, we use receivers at distances of <75 km from the targeted seismicity, through template matching. To improve the understanding of the mechanism(s) behind the earthquake initiation, we detail the evolution of the sequence associated to this earthquake, using waveform clustering and hypocenter relocation. Differences between foreshocks and aftershocks are revealed by this analysis. Moreover, distinct patterns associated to the different seismic activities are revealed. The observed behavior highlights a complex initiation process, which apparently starts on an adjacent antithetic fault. Finally, the aftershock activity comprises different clusters with distinct spatio-temporal patterns, which suggests that each cluster has distinct triggering mechanism(s).

The Alto Tiberina Fault system located in the Northern Apennines (Italy) consist of a low angle normal fault which radiates micro-seismicity on a constant rate and is assumed to host continuous creep. In the hanging wall, on top of the low angle normal fault, a network of syn- and antithetic high angle faults frequently hosts swarm seismic sequences, one of which has been associated to a transient aseismic deformation signal. To study in detail the dynamics related to the seismic and its relationships with aseismic deformation processes occurring in this fault system, we apply template matching on seismic data recorded at an array of borehole stations, to derive a high-resolution earthquake catalog. We then quantify the time and space clustering of the seismicity which reveals elevated clustering within the hanging wall during an aseismic deformation period. This reflects the complex evolution of aseismic slip together with the complexity of the shallow fault system. On the other hand, we observe a bimodal seismicity along the low angle normal fault, with continuous and diffuse seismicity, and rapid bursts which could suggest rapid fluid releases. Along the low angle normal fault, we additionally identify repeating earthquakes and model them assuming a creep model. Our results open the possibility for other models than the actual model of inter-seismic deformation to explain the seismicity along the Alto Tiberina low angle normal fault.