The interplay between slab dynamics and intraplate stresses in postcollisional times creates large near‐surface deformation, particularly in highly bent orogens with significant lateral variations in mechanical properties. This deformation is expressed through abnormal foredeep geometries and contrasting patterns of vertical movements. Intraplate folding is often the controlling mechanism, particularly when the orogenic belt is locked. The study of these tectonic processes in the SE Carpathians indicates a generalized subsidence period during latest Miocene–Pliocene times driven by the slab‐pull and an intraplate folding due to an overall Quaternary inversion. The latter accommodates ∼5 km ESE‐ward movement of this area with respect to the neighboring units, which creates complicated three‐dimensional deformation patterns potentially driven at a larger scale by the interaction between the Adriatic indentor and the entire Carpathians system. The lithospheric anisotropy inherited from the subduction times concentrates strain and induces large‐scale deformation far away from the active plate margins. This anisotropy is dynamic because of deep mantle processes related to the subducted slab during postcollisional times, such as thermal reequilibration or increase in slab dip.

The Danube Canyon is a large shelf-indenting canyon that has developed seaward of the late Pleistocene paleo-Danube valley. Mechanisms of canyon evolution and factors that controlled it are revealed by analyzing the morphology and the sedimentary structure of the canyon, as well as the main features of the continental margin around the canyon. This is based on investigation by swath bathymetry in the canyon area combined with different types of seismic data.The canyon is a major erosional trough with a flat bottom cut by an entrenched axial thalweg. The thalweg path varies from highly meandering to fairly straight in relation to the local gradient. Segments of the canyon are characterized by specific morphology, orientation and gradient along the axial thalweg. We interpret these segments in terms of canyon maturity. The sedimentary structure of the canyon documents an older phase of erosion followed by partial infilling, and thus attests for repeated cycles of canyon development.Canyon morphology is interpreted as a result of erosive sediment flows along the entrenched axial thalweg that caused downcutting into the canyon bottom and instability of the canyon walls, and hence enlargement of the canyon and expansion by headward erosion. During the last lowstand level of the Black Sea the canyon was located in an area of high sediment supply close to the paleo-Danube River mouths. This is indicated by buried fluvial channels on the shelf and by a wave-cut terrace associated with a water level situated about −90 m below the present level. We infer that erosive flows in the canyon resulted from hyperpycnal currents at the river mouths, probably favored by the low salinity environment that characterized the Black Sea during lowstand times. Other mechanisms could have contributed to trigger sediment failure along the canyon, such as instability related to the presence of shallow gas, or the effect of a deep fault.

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In front of the SE Carpathians Bend a very deep basin (Focşani Depression) developed in Miocene to Recent times. An important part of its subsidence occurred after the main stages of thrusting in the Carpathians. Apparently, the basin lies in the “wrong” place and evolved in the “wrong” time. In this study, we constrain its architecture and evolution by analyzing a large database consisting of more than 1000 km two‐dimensional seismic lines and more than 60 wells. Around 13 km thick, Badenian‐to‐Quaternary (<16.5 Myr) sediments were deposited in the central part of the Focşani Depression. During the Badenian (16.5–13 Myr), the foreland (south of Trotuş fault) underwent NE‐SW directed extension and NW trending basins opened in the eastern Moesian platform. A NW‐SE oriented area of subsidence stretched from the Transylvania basin through the Focşani Depression to the SE of the Moesian platform while thrusting was going on in the East European/Scythian platform, East Carpathians, and Getic Depression. Starting with the Sarmatian (13–10 Myr), the Focşani Depression depocenter moved out of the Carpathian belt coeval with the exhumation of the south and the East Carpathians north of the Trotuş fault. The basin became wider and was tilted toward the belt. Tilting was accompanied by dextral shearing mainly along the Intramoesian and Peceneaga‐Camena faults. After Sarmatian times, subsidence occurred practically only SSE of Trotuş fault. During Meotian‐Pontian (10–5 Myr), subsidence slowed down. Stronger, Pliocene‐Quaternary subsidence is coeval with normal faulting and shearing in Moesian platform. The western margin of the Focşani Depression was then tilted eastward, coeval with the exhumation of the bend zone and opening of the intramontane basins in the inner part of the belt.

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