The Corinth Rift, central Greece, enables analysis of early rift development as it is young (<5 Ma) and highly active and its full history is recorded at high resolution by sedimentary systems. A complete compilation of marine geophysical data, complemented by onshore data, is used to develop a high-resolution chronostratigraphy and detailed fault history for the offshore Corinth Rift, integrating interpretations and reconciling previous discrepancies. Rift migration and localization of deformation have been significant within the rift since inception. Over the last circa 2 Myr the rift transitioned from a spatially complex rift to a uniform asymmetric rift, but this transition did not occur synchronously along strike. Isochore maps at circa 100 kyr intervals illustrate a change in fault polarity within the short interval circa 620-340 ka, characterized by progressive transfer of activity from major south dipping faults to north dipping faults and southward migration of discrete depocenters at~30 m/kyr. Since circa 340 ka there has been localization and linkage of the dominant north dipping border fault system along the southern rift margin, demonstrated by lateral growth of discrete depocenters at~40 m/kyr. A single central depocenter formed by circa 130 ka, indicating full fault linkage. These results indicate that rift localization is progressive (not instantaneous) and can be synchronous once a rift border fault system is established. This study illustrates that development processes within young rifts occur at 100 kyr timescales, including rapid changes in rift symmetry and growth and linkage of major rift faults.

The style of extension and strain distribution during the early stages of intra-continental rifting is important for understanding rift-margin development and can provide constraints for lithospheric deformation mechanisms.The Corinth rift in central Greece is one of the few rifts to have experienced a short extensional history without subsequent overprinting.We synthesise existing seismic re£ection data throughout the active o¡shore Gulf of Corinth Basin to investigate fault activity history and the spatio -temporal evolution of the basin, producing for the ¢rst time basement depth and syn-rift sediment isopachs throughout the o¡shore rift. A major basin-wide unconformity surface with an age estimated from sea-level cycles at ca. 0.4 Ma separates distinct seismic stratigraphic units. Assuming that sedimentation rates are on average consistent, the present rift formed at 1^2 Ma, with no clear evidence for along-strike propagation of the rift axis.The rift has undergone major changes in relative fault activity and basin geometry during its short history. The basement depth is greatest in the central rift (maximum $3 km) and decreases to the east and west. In detail however, two separated depocentres 20^50 km long were created controlled by N-and S-dipping faults before 0.4 Ma, while since ca. 0.4 Ma a single depocentre (80 km long) has been controlled by several connected N-dipping faults, with maximum subsidence focused between the two older depocentres.Thus isolated but nearby faults can persist for timescales ca. 1 Ma and form major basins before becoming linked.There is a general evolution towards a dominance of N-dipping faults; however, in the western Gulf strain is distributed across several active N-and S-dipping faults throughout rift history, producing a more complex basin geometry.

The young Gulf of Corinth rift in centralGreece is an ideal place to study processes occurring during the initiation and early stages of continental extension. At the east end of the 100-km-long E-W rift, Holocene extension on N-dipping faults equates to geodetic extension rates. At the western end, however, estimated extension rates on N-dipping onshore faults account for only ~20%-40% of the geodetically measured rates (~10-15 mm/ yr). We use high-quality, multichannel, seismic refl ection and swath bathymetry data to investigate the tectonics of the western Gulf and quantify the contribution of offshore fault activity toward total-rift extension. Five major offshore faults generate the variable basement topography, and a ca. 0.4-Ma unconformity separates stratigraphy into two main packages. Basin-fi ll geometry indicates that during the early stages of subsidence of the offshore western Gulf, S-dipping faults were the dominant border-fault structure. This is still the case at the western end of the western Gulf; however, elsewhere, Ndipping faults on the south margin are now relatively more dominant and cause stratigraphy to tilt south. The temporally and spatially varying rift structure contrasts with the simple, consistently N-dipping, borderfault, half-graben geometry of the east Gulf of Corinth. Combined west Gulf offshore and onshore Holocene fault extension rates total 5-14.5 mm/yr, within the range calculated geodetically, and render enhanced slip on a low-angle detachment surface beneath the western Gulf unnecessary.