Abstract:

An experimental program for sedimentary simulation of flood turbidity current is described in this article.It is designed by using the sedimentation simulation test technology,collecting information concerning prototypes of flood turbidity sandbody,and integrating the forming environment and conditions for flood turbidity currents.The article also discusses the forming processes of flood turbidity current under different conditions,such as slope length and gradient,the initial velocity,mud-sand ratio and sand content,and etc;analyzes its deposition pattern;reveals the distribution and sedimentary characteristics of sand and muddy in flood turbidity current;dissects the controlling effect of lake-floor topography on flood turbidity sandbody and reveals the hydrodynamic mechanism for the formation and development of flood turbidity sandbody.The experimental results show that the flood turbidite deposition is influenced by various parameters,such as the slope gradient and elevation difference,the landform of the lake floor,the lake water level and the flow velocity,and that the contents of sand and mud in flood turbidity current determine its flow behaviour and sedimentary structure.

Key words: gravity flow, tractive current, flood turbidity current, flood deposit, slope zone, sedimentation si-mulation test