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The prompt identification of faults responsible for moderate‐to‐large earthquakes is fundamental for understanding the likelihood of further, potentially damaging events. This is increasingly challenging when the activated fault is an offshore buried thrust, where neither coseismic surface ruptures nor GPS/InSAR deformation data are available after an earthquake. We show that on 9 November 2022, an Mw 5.5 earthquake offshore Pesaro ruptured a portion of the buried Northern Apennines thrust front (the Cornelia thrust system [CTS]). By post‐processing and interpreting the seismic reflection profiles crossing this thrust system, we determined that the activated fault (CTS) is an arcuate 30‐km‐long, NW‐SE striking, SW dipping thrust and that older structures at its footwall possibly influenced its position and geometry. The activation of adjacent segments of the thrust system is a plausible scenario that deserves to be further investigated to understand the full earthquake potential of this offshore seismogenic source. Plain Language Summary: The Northern Apennines chain is characterized by thrust faults running from the Po Plain to the Adriatic Sea on the northeastern side of peninsular Italy. These thrusts are buried below ≈2,000 m cover of Plio‐Pleistocene deposits. Controversies arose about these thrust faults' activity and earthquake potential based on their hidden geological signature and the scanty seismicity that could be associated with them. The earthquake (magnitude 5.5) that occurred on 9 November 2022, offshore Pesaro revived this argument. In this work, we analyze the geological structure of the crustal volume affected by the seismic sequence, exploiting seismic reflection profiles and well‐log data to identify the earthquake causative fault. Our results demonstrate that the earthquake ruptured a well‐known fault of the Northern Apennines' buried thrust front, supporting that it is indeed active and seismogenic. The size and architecture of this thrust front suggest that it could generate even larger earthquakes (Mw > 6.5). This type of geological study is instrumental to understanding the geometry of earthquake faults, particularly in offshore areas, because they constitute reliable inputs for earthquake hazard models and, when done promptly after an earthquake, provide key elements for other studies on the seismic source and the unfolding of the ongoing seismic sequence. Key Points: 9 November 2022, earthquake consistent with activity of the Cornelia thrust, a fault system running off the central Adriatic coastThe seismic reflection profiles in the area allowed for delineating the thrust and its earthquake potential with a much finer resolutionThe properties of the causative fault suggest that the activation of adjacent segments is a plausible scenario that deserves consideration [ABSTRACT FROM AUTHOR]

Abstract: The deep structures of the Central–Southern Apennines are analysed on the basis of the regional component of gravity anomalies, obtained applying a stripping technique. This procedure allows the accurate removal of the gravimetric effect of the three-dimensional shallow (within the first 10km) geological bodies from the observed Bouguer anomaly. The resulting anomaly map differs quite significantly from the Bouguer anomaly map, providing new constraints on the nature of the deeper part of the crust and on the upper mantle. The stripping reveals that the regional gravity lows are shifted westward in comparison with Bouguer anomaly lows. Moreover, the gravimetric pattern indicates a lack of cylindrism for the deep structures of the Apennine Chain, which in the study area can be roughly divided into three main segments. The observed differences between the gravity anomalies pattern of the Central Apennines and that of the Southern Apennines are marked. The integration of gravimetric results with other geophysical data suggests that: (i) a ramp-dominated style for the buried Apulia (Adria) units and part of the underlying basement is compatible with gravimetric data and (ii) most of the regional gravity anomalies in the Central Apennines seem to originate within the lower crust. [Copyright &y& Elsevier]

Abstract: Geologic interpretation of seismic data along the eastern half of the CROP 11 deep seismic reflection profile, running across the central Apennines, indicates that the Adriatic Moho deepens gradually from 34 km in the foreland areas to 47 km beneath the core of the belt. This deepening is in agreement with local Moho depths estimated from teleseismic receiver functions at several stations installed along the CROP 11 profile. On the contrary, DSS (Deep Seismic Soundings) data image the Moho at shallower depths. The deepening of the Adriatic Moho illustrated in this paper supports the westward downgoing of a portion of Adriatic continental crust and is consistent with the regional gravity anomalies, provided that very high-density rocks are present above the Moho at the core of the central Apennine belt. We discuss geophysical and geologic data in the framework of alternative models of delamination of the Adriatic crust at different depth. [Copyright &y& Elsevier]