Three-dimensional Numerical Simulation of the Influence of Slope on Turbidity Flow and Deposition

The first self-developed Simusoft software with intelligent grid generation was used to generate three-dimensional model grids of underwater straight trapezoid and curved trapezoid channels. The influences of slope on turbidity current velocity, turbidity current density, deposition thickness and sediment particle size distribution in straight and curved trapezoid channels were simulated and analyzed. The results show that with the increase of slope, the flow velocity of both straight and curved channels is non-linear , and the maximum flow velocity of vertical section tends towards the bottom bed. The turbidity density in the straight channel reaches the maximum at the slope break, and the turbidity head density decreases faster with the increase of the slope. The turbidity density in the curved channel also increases with the increase of the slope, and the turbidity overflow is gradually enhanced. The sediment amount of multiple turbidity-current events in low slope break channels gradually reduce from the upper stream to the lower stream. While in the high slope break channels, the upper stream erosion increases and the deposition increases after the slope break. This study has a certain reference function for inferring the formation environment of turbidite based on the observation of turbidite characteristics, and then determining the relevant turbidity current mechanism and possible reservoir size.