Martin Muravchik

AUV High-Resolution Bathymetry Of Axial-Transverse Drainage Interaction In The Structurally Controlled Subaqueous Channels In The Gulf Of Corinth, Corinth Rift, Greece

Martin Muravchik

New high-resolution (submeter) bathymetric data, acquired using an AUV Hugin 1000, from the Gulf of Corinth, Greece reveals unprecedent detail on the interaction between transverse and axial submarine channels in an active rift. The dataset presented was acquired using the EM2040 Multibeam Echosounder on the AUV at 300 and 400 kHz, navigating between 100 and 50 m above the seafloor. The surveyed area lies towards the western part of the Gulf of Corinth, offshore of the coastal towns of Aigio and Akrata. The area is characterized by the development of coarse-grained deltas sourced by north-flowing rivers draining the mountain ranges. The seafloor morphology shows the presence of active canyons, ca. 100 m deep, draining from the delta fronts towards north in water depths between 100 to 600 m, interacting with an axial trunk channel in water depths between 550 to 650 m, draining towards east, and which looses its expression in water depths between 700 and 800 m. These submarine channels show a strong structural control in both position and orientation by the normal faulting affecting the present-day Gulf of Corinth sea-floor. This survey includes the mapping of the three submarine tributaries derived from the Soulinous, Kerinitis and Vouraikos deltas and their link into the axial trunk channel. The survey shows the presence of large erosional scours in the axial channel, at the confluence with of some of the tributaries. This, together with the pervasive erosional features developed on the axial channel base and margins towards its exit onto the basin-floor, reveal the development of complex erosive flow patterns due to changes in the gradient of the sea-floor and the orientation of channel margins at the confluences between the tributaries and the axial channel.