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We present a new 3D geologic model for the architecture and Cenozoic tectonic evolution of the Tuz Gölü Basin, a major sedimentary basin in the Central Anatolian orogenic plateau. This model is grounded on 7 depth-converted seismic reflection profiles in combination with the analysis of backstripped subsidence curves, isochore maps, and a palinspastically restored cross-section. Two stages of basin formation are detected during Cenozoic times. During the Palaeogene, around 2 km of basement subsidence led to the development of a sag basin broader than the present basin in the absence of bounding faults. After a period of uplift and erosion, sedimentation restarted by Tortonian times. Up to 3.5 km of post-Palaeogene sediments were deposited in relation to this second regional subsidence phase, which continued possibly well into the Pliocene. During this time, the 2 main fault systems found in the area, the Tuz Gölü and the Sultanhanı faults, developed as south-west dipping, NW-SE striking, normal faults. At some time in the Late Miocene-Early Pliocene, during regional subsidence, a previously unreported phase of contraction occurred, which led to the development of a north-east-vergent thrust sheet, the culmination of which forms the morphologic ridge to the east of the Tuz Gölü Lake. This structure presently divides the previously continuous Tuz Gölü Basin. Finally, minor extensional reactivation occurred. At the regional scale, the pre-Late Miocene subsidence is coeval with the initiation of volcanism in the Central Anatolian Volcanic Province and marine carbonate deposition in southern Turkey, and the latest Miocene shortening is (partly) contemporaneous with the onset of uplift in the same region. [ABSTRACT FROM AUTHOR]

This review shows how collective analysis of morphotectonic elements on uplifting rift margins can constrain the mechanical behaviour of continents during early rifting. This is shown for the modern Corinth Rift, one of the fastest-extending and most seismically active continental regions worldwide. We reconstruct the growth of the normal fault system that accommodates most of the rift strain and the uplift of the rift margin it bounds, from onset to present and at rift scale. Our approach allows first-order inferences on the mechanics and evolution of the rift, and can be used in other areas of early continental rifting. We review and re-assess known geologic evidence in the Corinth Rift, and compile morphotectonic elements into a new map. We analyse the rift topo-bathymetry, and the footwall relief, river catchments and tectonic knickpoints in its uplifting margin. We also review studies that constrain the growth of normal faults using morphotectonic elements in their footwall, and propose a novel theoretical framework to reconstruct fault time-evolution during early rifting. We couple known and new data to derive fault displacement profiles in time, and use the theoretical framework to infer the history of growth and linkage of rift border faults, in turn constraining rift growth mechanics and evolution. Our rift-scale morphotectonic investigation shows that the current rift-bounding faults are kinematically coherent at depth and constitute a fault >80 km in length. This composite master fault grew along-strike from the rift centre, linking and integrating individual fault segments that developed co-linearly at earlier times. The observed fault elastic flexure, footwall relief wavelength and high uplift and slip rates throughout the rift margin suggest the border fault is steep and highly localized in strain, and transects the entire seismogenic layer growing in a long-term strong elastic lithosphere. Integration of previous and our new findings suggest the Corinth Rift evolved in two distinct extensional phases. These extensional phases are delimited by the fast, overwriting growth of the new rift-forming fault, that switched rift mechanics in a ~300 kyr timespan, and controls rift evolution thereafter. The new rift-forming fault enlarges the modern rift as an asymmetric half-graben, along and across strike, superimposed onto the preceding ~4 My distributed extension. [ABSTRACT FROM AUTHOR]

Better characterizations of the evolution of active normal faults is key to understand crustal mechanics and dynamics, and thus, continental tectonics. We propose a simple theoretical framework to characterize the mode of growth of active crustal faults from the geomorphology of their extensional footwalls. The framework is based on the shape of fault displacement profiles and the height of tectonic knickpoints in footwall rivers that are expected, barring complicating factors, in response to different scenarios of active fault linkage and growth. The framework provides inferences on the relative onset of activity for individual fault segments and their linkage mode (simple, directed or propagated) in active colinear faults, and we use it to understand the evolution of the active faults bounding the uplifting shoulder of the Corinth Rift. We use coeval markers of past sea levels and the present-day footwall relief as proxies to fault displacement profiles in time and tectonic knickpoints in river trunks draining the extensional footwall orthogonally towards the bounding faults. Our results imply that the individual fault segments of the rift bounding system are a kinematically-coherent composite fault, and that the fault grew along-strike from the rift centre linking and integrating fault segments by propagation along their strike. [ABSTRACT FROM AUTHOR]