Bed instability generated by turbidity currents

Abstract

Once relatively fine sediment is entrained into water on the ocean floor of the continental shelf or the continental slope, water near the ocean floor increases its density due to the entrained sediment, and starts to flow in the downslope direction. This density flow is called a turbidity current in particular. A turbidity current has unimaginably high capabilities for erosion of the bed and sediment transport, and therefore, it is one of the major agents for the formation of submarine morphology such as submarine canyons and bedforms. As turbidity currents transport not only sediment also a large amount of organic matters originated in the continental areas to the deep ocean floor, they are one of the most essential processes for the generation of petroleum and methane hydrate. In addition, turbidity currents cause destructive damages on submarine infrastructure such as submarine cables. Therefore, study on turbidity currents is important from view points of the maintenance of submarine infrastructure.