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We present an interpretation of the eastern half portion of the CROP 11 line, a deep reflection seismic profile 265 km long that cuts across the central Apennines from the Tyrrhenian coast to the Adriatic coast. In the study area the line cuts across a pile of thrust sheets that underwent tectonic transport between the Messinian and the Pleistocene. In its easternmost part, the line runs through the Plio‐Pleistocene deposits of the Adriatic foredeep. In the foreland region the CROP 11 line integrates previous information on the crustal structure derived from petroleum exploration and from deep seismic sounding refraction experiments. In particular, the CROP 11 line confirms the existence of a very thick sedimentary sequence underlying the Mesozoic‐Tertiary carbonates of the Apulia Platform interpreted as the Paleozoic‐Triassic sedimentary cover of a pre‐Cambrian crystalline basement. In the mountain chain, where the base thrust of the orogenic wedge reaches a depth of about 25 km, this sedimentary sequence appears to be the deepest geological unit incorporated in the thrust system. This interpretation of the CROP 11 profile suggests an unusual thin‐skin tectonic style implying the detachment from the original basement and the incorporation in the post‐Tortonian tectonic wedge of a very thick Paleozoic‐Triassic sedimentary sequence possibly affected by low‐grade metamorphism in the lower part. Other new suggestions from the CROP 11 seismic data concern the origin of the Fucino basin, one of the most remarkable Plio‐Pleistocene intramontane basins. The normal faults bordering this structural depression, as other important normal faults present in the central Apennines (e.g., the Caramanico fault system in the Majella region), seem to have been controlled by gravitational‐collapse processes driven by uplift during crustal shortening rather than by a generalized extension subsequent to the Apennine compression, as usually reported in the geological literature. If this interpretation is correct, the strong seismic activity in correspondence to the Apennine watershed may be related to the very recent increase in the structural relief caused by an out‐of‐sequence propagation of the active thrusts.

Starting from 24 August 2016, a long seismic sequence, including nine Mw > 5.0 earthquakes, struck a wide area of the Central Italy. A large amount of geological, geodetic, and seismological data envisages a complex system of NNW‐SSE trending, seismogenic normal faults. These active tectonic structures are well known at the surface and consistent with previous seismotectonic studies. In order to improve the comprehension of the seismotectonic framework of this seismic sequence, we provide a novel reconstruction of the subsurface geology of the area close to the Norcia Mw 6.5 mainshock (30 October 2016), based on previously unpublished seismic reflection profiles and available geological data. All the data have been synthesized along a 47 km long, WSW‐ENE trending geological cross section, interpreted down to a depth of 12 km. Comparing the subsurface geological model with the available seismological data, we find that the majority of seismicity is confined within the sedimentary sequence and does not penetrate the underlying basement. The basement has been constrained at depths of 8 to 11 km and coincides with the cutoff of the seismicity. We have also traced the trajectories of the seismogenic normal faults activated during this seismic sequence, reconciling the high‐angle (dip>65°) normal faults exposed at the surface, with their angle (dip < 50°) at hypocentral depths. The results of this study may be useful for better understanding the rheological properties of the seismogenic rock volume, as well as the coseismic deformations of the topographic surface observed by geodetic techniques and field mapping.

The Late Pleistocene/Holocene Tiber delta succession represents the most recent and one of the best preserved, high-frequency/low-rank depositional sequences developed along the Latium continental margin of the Italian peninsula. Several previous studies have established a robust data set from which it has been possible to describe the stratigraphic architecture of the entire Tiber depositional sequence from the landward to seaward sectors and over a distance of 60 km. The Tiber depositional sequence shows many characteristics found in other Late Pleistocene to Holocene deltaic and coastal successions of the Mediterranean area. The stratigraphic architecture of the Tiber depositional sequence is controlled mainly by glacioeustasy, although factors such as tectonic uplift, volcanism and subsidence, exert an influence at a local scale. The resulting depositional model allowed discussion of some important points such as: (1) the genesis of the Tiber mixed bedrock-alluvial valley, extending from the coastal plain to the innermost portion of the shelf, recording (i) multiple episodes of incision during relative sea-level fall, and (ii) a downstream increase of depth and width of the valley during the base-level fall and the subsequent base-level rise; (2) the different physical expression of the Tiber depositional sequence boundary from landward to seaward, and its diachronous and composite character; (3) the maximum depth reached by the Tiber early lowstand delta at the end of the sea-level fall is estimated at ca 90 m below the present sea-level and not at 120 m as suggested by previous works; (4) the backward position of the Tiber late lowstand delta relative to the deposit of early lowstand; (5) the change of the channel pattern and of the stacking pattern of fluvial deposits within the Lowstand Systems Tract, Transgressive Systems Tract and Highstand Systems Tract. All of these features indicate that the Late Pleistocene/ Holocene Tiber delta succession, even if deposited in a short period of time from a geological point of view, represents the result of the close interaction among many autogenic and allogenic factors. However, global eustatic variations and sediment supply under the control of climatic changes can be considered the main factors responsible for the stratigraphic architecture of this sedimentary succession, which has been heavily modified by human activity only in the last 3000 years. 1886