Bedrock river channel steepness index can be used to infer relative differences in rock uplift rates across a landscape, given uniform lithology and climatic forcing. River incision, E, is

""Calabria represents an ideal site to analyze the. topography of a subduction zone as it is located on. top of a narrow active Wadati‐Benioff zone and shows. evidence of rapid uplift. We analyzed a pattern of surface. deformation using elevation data with different. filters and showed the existence of a long wavelength. (>100 km) relatively positive topographic signal at the. slab edges. The elevation of MIS 5.5 stage marine. terraces supports this pattern, although the record is. incomplete and partly masked by the variable denudation. rate. We performed structural analyses along. the major active or recently reactivated normal faults. showing that the extensional direction varies along the. Calabrian Arc and laterally switches from arc‐normal,. within the active portion of the slab, to arc‐oblique or. even arc‐parallel, along the northern and southern slab. edges. This surface deformation pattern was compared. with a recent high resolution P wave tomographic. model showing that the high seismic velocity anomaly. is continuous only within the active Wadati‐Benioff. zone, whereas the northern and southwestern sides are. marked by low velocity anomalies, suggesting that. large‐scale topographic bulges, volcanism, and uplift. could have been produced by mantle upwelling. We. present numerical simulations to visualize the threedimensional. mantle circulation around a narrow retreating. slab, ideally similar to the one presently subducting. beneath Calabria. We emphasize that mantle upwelling. and surface deformation are expected at the edges of. the slab, where return flows may eventually drive decompression. melting and the Mount Etna volcanism."

[1] The Sila Massif in the Calabrian Arc (southern Italy) is a key site to study the response of a landscape to rock uplift. Here an uplift rate of $1 mm/yr has imparted a deep imprint on the Sila landscape recorded by a high-standing low-relief surface on top of the massif, deeply incised fluvial valleys along its flanks, and flights of marine terraces in the coastal belt. In this framework, we combined river longitudinal profile analysis with hillslope erosion rates calculated by 10 Be content in modern fluvial sediments to reconstruct the long-term uplift history of the massif. Cosmogenic data show a large variation in erosion rates, marking two main domains. The samples collected in the high-standing low-relief surface atop Sila provide low erosion rates (from 0.09 AE 0.01 to 0.13 AE 0.01 mm/yr). Conversely, high values of erosion rate (up to 0.92 AE 0.08 mm/yr) characterize the incised fluvial valleys on the massif flanks. The analyzed river profiles exhibit a wide range of shapes diverging from the commonly accepted equilibrium concave-up form. Generally, the studied river profiles show two or, more frequently, three concave-up segments bounded by knickpoints and characterized by different values of concavity and steepness indices. The wide variation in cosmogenic erosion rates and the non-equilibrated river profiles indicate that the Sila landscape is in a transient state of disequilibrium in response to a strong and unsteady uplift not yet counterbalanced by erosion. Be erosion rates and river longitudinal profile analysis, Tectonics, 31, TC3007,

The opening of the Tyrrhenian Sea has been punctuated by short-lived episodes of oceanic\ud accretion on separate small backarc basins during early Pliocene (Vavilov basin) and early\ud Pleistocene (Marsili basin) time. These spreading pulses are related to slab rollback and are\ud synchronous with the reduction of the subduction zone width during the formation of the\ud narrow Calabrian arc. Using laboratory models, we investigated the long-term and transient\ud effects of the reduction of slab width on the subduction kinematics. We found that the abrupt\ud reduction in slab width results in a pulse of acceleration of the trench retreat velocity, as the\ud balance between driving and resisting forces acting on the slab is temporarily modifi ed. Our\ud fi ndings also show that the time scale and amplitude of spreading observed in the Tyrrhenian\ud Sea can be experimentally fi tted if the scaled viscosity of the uppermost part of the mantle\ud ranges between 1019 and 1020 Pa s

39Central Iran provides an ideal region to study the long-term morphotectonic response to the 40 nucleation and propagation of intraplate faulting. In this study, a multidisciplinary approach 41 that integrates structural and stratigraphic field investigations with apatite (U+Th)/He (AHe) 42 thermochronometry is used to reconstruct the spatio-temporal evolution of the Kuh-e-Faghan 43 As demonstrated by regional and global stress field maps, in-plane stresses can be 65