On the relationship between seismogenic sources and statistical features of seismicity

Seismic events take place along weak interfaces inside brittle crustal volumes showing a wide variability in their intensity, ranging from aseismic creep to large earthquakes, in their type and in their spatial and temporal organization. The structural properties of seismogenic sources play a key role in shaping the aforementioned features of telluric activity. Fault slip dynamics depends on several physical properties of rock physics and geological environment. Regarding the latter, we focus on two kinds of differences that have been highlighted so far: tectonic settings and on-fault vs diffuse sources. Unlike others, peculiarities are in these cases transversal, regarding structural features of the fault zone (Zaccagnino & Doglioni, 2022), fluid circulation, moment tensors and statistical parameters of seismic sequences (Zaccagnino et al., 2022). We look for a comprehensive view of such phenomena for an advanced understanding of seismicity on the light of a simple physical model. As a first step, we analyse the spatial and temporal organization of seismic time series using a quantitative approach based on fractal, entropic and clustering properties. Afterwards, we connect it to the physical parameters of earthquakes hosted in the same tectonic setting for getting new insights about their mechanics. Our model explains the mathematical relationship between properties of in-fault and off-fault seismicity being the first featured by lower b-value, stress drop, fractal dimension of hypocentral time series and larger corner magnitudes. Differences between tectonic settings are described using the same framework. We also analyse the relationship between fault maturity and properties of hosted seismicity. Our approach can provide information about the long-term seismic behaviour of fault systems, which may be extremely valuable if seismic networks are recently development and paleoseismological studies are missing or poorly constrained. References Zaccagnino, D. and Doglioni, C.; 2022: The impact of faulting complexity and type on earthquake rupture dynamics. Commun. Earth Environ., 3(1), 1-10. Zaccagnino D., Telesca L. and Doglioni C.; 2022: Scaling properties of seismicity and faulting. Earth Planet. Sci. Lett., 584, 117511. *Davide Zaccagnino contact: davide.zaccagnino@uniroma1.it