Unravelling tectonic and climatic controls on Late Quaternary Corinth Rift stratigraphy

The Earth's surface is constantly reshaped by climatic and tectonic forces, driving the erosion, transport, and deposition of sediments. Sediment routeing systems trace the pathways that carry sediment from its source to its final sink. Both deep-water sinks and transfer zones serve as "tape recorders," capturing interactions between tectonics, climate, and lithology, though the reliability of these records in documenting events is debated.
This study examines the Gulf of Corinth, Greece, a region characterised by a deep rift basin adjacent to a transport-limited catchment, with narrow shelves and steep basin margins shaped by normal fault systems, including a fault-bounded canyon-fed submarine fan system; the Sythas canyon and fan. By integrating topographic, geophysical, and IODP borehole data, this research analyses processes and controls within the transfer zone and sink.
Findings indicate significant variations in sediment flux between glacial and interglacial periods, including stadial and interstadial periods, with the Holocene showing an anomalously high flux not fully explained by climatic factors. Human activities are considered to have influenced erosion and sediment transport rates. The Sythas submarine canyon-mouth transition zone (CaMTZ) is documented in detail. An overall basinward distribution of erosional (incipient channels and scours) to depositional (sediment waves) bedforms, which is complicated by erosional bedforms on overbank settings, is seen prior to a transition into basin-floor lobes. Complexities arise in distinguishing external factors affecting subaerial and submarine drainage profiles. Tectonics primarily shape subaerial profile convexities, while lithological variations influence steepness. In submarine profiles, faulting results in steep canyons. Seascape morphometries correlate with climate proxies, whereas subaerial profiles show weaker climate correlations due to delayed responses from extended drainage pathways.
Overall, the findings highlight that environmental signals can be transferred into deep-water sedimentary records, and that tectonics mainly dictate channel profile in the transfer zone of a source to sink system (S2S), while climate strongly influences sediment supply, and their deposition rates in the sink.