![]() We document a strait divided in a centre zone and 2 adjacent dune-bedded strait zones The centre is an active horst where sediment bypass occurred. To do so, we used field observations associated with a 3D model built from drone imaging. Therefore, this exceptionally well-exposed site could be used as an analogue to study tidal straits after the definition of its stratigraphic architecture, sedimentology and structure. A former strait naturally connecting the gulf with the Aegean Sea is assumed in this area. The man-made Corinth canal connects the Aegean Sea with the Corinth Gulf while displaying high steep walls allowing to study the sedimentological structure of this area. The collective results confirmed that in the Central Apennines, conditions of dynamic equilibrium are often not met, and that the persistence of transient perturbations induced by tectonics should be accounted for. Considering the 2009 L’Aquila earthquake coseismic rupture, we observe that the younger transience on the Raiale River longitudinal profile, if it is of tectonic origin, could have only been produced by much larger seismic events (i.e., Mw > 6.5) than those documented in the area by paleoseismological investigations. Last, the analysis of the modern Raiale River longitudinal profile denoted an ungraded status, with two main knickzones that we interpret as transient forms due to tectonic perturbations, likely triggered by activity of the Paganica Fault during the end Early Pleistocene and the Late Pleistocene. ![]() This denudation is in keeping with the drainage incision, suggesting a non-steady state for the fault footwall topography and a dominance of relief growth. In parallel, using terrestrial cosmogenic nuclides, a denudation rate of 0.02–0.04 mm/a was measured on the summit of the footwall block. Terrace dating yielded a minimum incision rate of 0.25 ± 0.02 mm/a, which only partially compensates the footwall uplift and can thus be considered as a minimum value for the Paganica Fault throw rate, which could reach up to ~0.45 mm/a. ![]() The Raiale River downcutting formed five Middle–Late Pleistocene fluvial terraces, that, along with absolute optically stimulated luminescence (OSL) dating, allowed the identification of paleolongitudinal profiles with a diverging downstream configuration. Starting from the late Early Pleistocene–Middle Pleistocene, fluvial dissection was mainly due to marked river downcutting triggered by significant activity of the Paganica Fault, which caused progressive base-level lowering. Using morphostratigraphy and paleomagnetic analysis, the Plio–Pleistocene morphotectonic evolution of the area was reconstructed, comprising an ancient continental basin and paleolandforms that predate the footwall incision. The aim was to constrain the active tectonics by studying the Raiale River that orthogonally crosscuts the fault trace, where it provides a useful geomorphological marker of long-term fluvial incision and footwall uplift. The footwall of the surface rupturing Paganica normal fault, the source of the 2009 L’Aquila earthquake (Mw 6.1) in the Central Apennines (Italy), was investigated using integrated geological and geomorphological approaches. We interpret the initiation of E‐W extension as the result of a change in plate boundary conditions, in response to either propagation of the North Anatolian Fault, incipient collision with the African plate, mantle dynamics or a combination thereof. Our findings on‐ and offshore suggest that E‐W extension is the dominant mode of regional active upper crustal deformation, and N‐S normal faults accommodate most, if not all of the uplift on Kythira. Guided by simple landscape evolution models, we interpret the coastal morphology as the result of initial stability or of slow, gradual sea‐level drop since ∼2.8–2.4 Ma, followed by faster uplift since ∼1.5–0.7 Ma. Subsequent marine regression of ∼300–400 m and minor E‐W tilt are recorded in ∼12 marine terrace levels for which we estimate uplift rates of ∼0.2–0.4 mm/yr. We find that the Tortonian‐Pliocene stratigraphy in Kythira records ∼100 m of subsidence, and a wide coastal rasa marks the ∼2.8–2.4 Ma maximum transgression. We present a morphotectonic map of the island, together with new biostratigraphic dating and detailed analyses of active fault strikes and marine terraces. The remarkable geology and geomorphology of Kythira Island, in the southwestern Hellenic forearc, allow for a detailed tectonic reconstruction since the Late Miocene. Multiple areas of the Hellenic Forearc have been uplifting since Plio‐Quaternary times, yet spatiotemporal characteristics and sources of this uplift are poorly resolved. Several crustal and lithospheric mechanisms lead to deformation and vertical motion of the upper plate during subduction, but their relative contribution is often enigmatic.
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