The onshore central Corinth rift contains a syn-rift succession >3 km thick deposited in 5-15 kmwide tilt blocks, all now inactive, uplifted and deeply incised. This part of the rift records upward deepening from fluviatile to lake-margin conditions and finally to sub-lacustrine turbidite channel and lobe complexes, and deep-water lacustrine conditions (Lake Corinth) were established over most of the rift by 3.6 Ma. This succession represents the first of two phases of rift development -Rift 1 from 5.0-3.6 to 2.2-1.8 Ma and Rift 2 from 2.2-1.8 Ma to present. Rift 1 developed as a 30 kmwide zone of distributed normal faulting. The lake was fed by four major N-to NE-flowing antecedent drainages along the southern rift flank. These sourced an axial fluvial system, Gilbert fan deltas and deep lacustrine turbidite channel and lobe complexes. The onset of Rift 2 and abandonment of Rift 1 involved a 30 km northward shift in the locus of rifting. In the west, giant Gilbert deltas built into a deepening lake depocentre in the hanging wall of the newly developing southern border fault system. Footwall and regional uplift progressively destroyed Lake Corinth in the central and eastern parts of the rift, producing a staircase of deltaic and, following drainage reversal, shallow marine terraces descending from >1000 m to present-day sea level. The growth, linkage and death of normal faults during the two phases of rifting are interpreted to reflect self-organization and strain localization along co-linear border faults. In the west, interaction with the Patras rift occurred along the major Patras dextral strike-slip fault. This led to enhanced migration of fault activity, uplift and incision of some early Rift 2 fan deltas, and opening of the Rion Straits at ca. 400-600 ka. The landscape and stratigraphic evolution of the rift was strongly influenced by regional palaeotopographic variations and local antecedent drainage, both inherited from the Hellenide fold and thrust belt.

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[1] Organic-rich sediments are the salient marine sedimentation product in the mid-Cretaceous of the ocean basins formed in the Mesozoic. Oceanic anoxic events (OAEs) are discrete and particularly organic-rich intervals within these mid-Cretaceous organic-rich sequences and are defined by pronounced carbon isotope excursions. Marine productivity during OAEs appears to have been enhanced by the increased availability of biolimiting nutrients in seawater due to hydrothermal alteration of submarine basalts in the Pacific and protoIndian oceans. The exact mechanisms behind the deposition of organic-rich sediments in the mid-Cretaceous are still a matter of discussion, but a hypothesis which is often put forward is that their deposition was a consequence of the coupling of a particular paleogeography with changes in ocean circulation and nutrient supply. In this study, we used a global coupled climate model to investigate oceanic processes that affect the interbasinal exchange of nutrients as well as their spatial distribution and bioavailability. We conclude that the mid-Cretaceous North Atlantic was a nutrient trap as a consequence of an estuarine circulation with respect to the Pacific. Organic-rich sediments in the North Atlantic were deposited below regions of intense upwelling. We suggest that enhanced productivity during OAEs was a consequence of upwelling of Pacificderived nutrient-rich seawater associated with submarine igneous events.

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