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Deep fluid circulation likely triggered the large extensional events of the 2016–2017 Central Italy seismic sequence. Nevertheless, the connection between fault mechanisms, main crustal‐scale thrusts, and the circulation and interaction of fluids with tectonic structures controlling the sequence is still debated. Here, we show that the 3D temporal and spatial mapping of peak delays, proxy of scattering attenuation, detects thrusts and sedimentary structures and their control on fluid overpressure and release. After the mainshocks, scattering attenuation drastically increases across the hanging wall of the Monti Sibillini and Acquasanta thrusts, revealing fracturing and fluid migration. Before the sequence, low‐scattering volumes within Triassic formations highlight regions of fluid overpressure, which enhances rock compaction. Our results highlight the control of thrusts and paleogeography on the sequence and hint at the monitoring potential of the technique for the seismic hazard assessment of the Central Apennines and other tectonic regions. Plain Language Summary There is widespread evidence that the Amatrice‐Visso‐Norcia seismic sequence (2016–2017, Central Italy) was triggered by fluid circulation across the Apennine Chain. However, how, and why fluids migrated across the fault network is still under debate. Seismic attenuation describes how seismic waves lose energy during their propagation. When used as an imaging attribute, it has demonstrated the potential to recover the spatial extension and mechanisms of fracturing and fluid movement across volcanoes and faults. Here, we map scattering attenuation through the peak delay measurements in 3D before (2013–2016) and during the 2016–2017 sequence. Scattering attenuation separated fractured zones from regions of compaction, controlled, before and during the sequence by thrusts and lithological differences. High scattering (strong fracturing) increases through time due to intense fracturing, while low scattering (higher compaction of the rocks) marks areas where earthquakes will occur. Our results highlight the importance of the main thrusts, as they separate compartments of the shallow crust characterized by different scattering attenuation anomalies, the Triassic deposits in fluid accumulation, and subsequent triggering of normal faults. Key Points Scattering attenuation detects the control of thrusts and lithology on post‐seismic fracturing and fluid migration during the AVN sequence Overpressurized fluids compact low‐scattering rocks at thrusts' roots before earthquakes Detecting fluid overpressure and fracturing suggests an unexploited monitoring potential of scattering attenuation

Bedding-perpendicular joints striking parallel (longitudinal) and perpendicular (transverse) to both the axis of the hosting anticline and the trend of the foredeep-belt system are widely recognized in fold-and-thrust belts. Their occurrence has been commonly attributed to folding-related processes, such as syn-folding outer-arc extension, although they can also be consistent with a pre-folding foredeep-related fracturing stage. Here we report the pre-folding fracture pattern affecting the Pietrasecca Anticline, in the central Apennines (Italy), resolved by a detailed field structural analysis. Field observations, scan-lines and interpretation of virtual outcrops were used to study the intensity, distribution and the orientations of fracture pattern along the anticline. The fracture pattern of the Pietrasecca Anticline consists of longitudinal and transverse joints, oriented approximately perpendicular to bedding, and of a pre-folding longitudinal pressure-solution cleavage set, which is oblique to bedding regardless of the bedding dip. Cross-cutting relationships show that joints predated the development of the pressure-solution cleavage. Furthermore, joint intensity does not relate to the structural position along the anticline. Taken together, these observations suggest that jointing occurred in a foredeep environment before the Pietrasecca Anticline growth. Our work further demonstrates that joints striking parallel and orthogonal to the main fold axis do not necessarily represent syn-folding deformation structures.

The Po Plain (Italy) is one of the most densely populated and productive regions of Europe, characterized by a flourishing economy (also linked to strategic subsurface resources) and several world cultural and natural heritage sites. The coupling of socio-economic interests with geological hazards (i.e. seismic, subsidence, and flooding hazards) in this area requires accurate knowledge of the subsurface geology, the active geological processes, and the impact of human activities on natural environments to mitigate the potential natural and anthropic risks. Most data unveiling the subsurface geology of this region were produced by the hydrocarbon exploration industry. Indeed, the Po Plain hosts many hydrocarbon fields that have been discovered since the early 1950s, giving rise to the subsurface exploration through extensive seismic reflection surveys and drilling of numerous deep wells. In this work, geological and geophysical data from 160 deep wells drilled for hydrocarbon exploration and/or exploitation purposes in the Po Plain and in the facing northern Adriatic Sea have been collected and digitized along with several published geological cross-sections and maps. These data have been used to reconstruct the overall subsurface 3D architecture and to extract the physical properties of the subsurface geological units. The digitized data are suitable to be imported into geo-software environments so as to derive the geophysical and mechanical properties of the geological units for a wealth of applied and scientific studies such as geomechanical, geophysical, and seismological studies. The integrated dataset may represent a useful tool in defining regional first-order strategies to ensure the safety of the urbanized areas and human activities and to reduce natural and anthropic risks that may affect this crucial region of Europe. In particular, the data collected would be useful to highlight sensible areas where data collection and more detailed studies are needed. Nowadays, such issues are particularly relevant for the underground industry development related to the increasing interest in possible CO2 and hydrogen underground storage, which can play a fundamental role in the energy transition process towards decarbonization goals. The full dataset is available at the following link: https://doi.org/10.5281/zenodo.8126519 (Livani et al., 2023).