Modeling of Flow and Morphodynamics of Sinuous Submarine Channels

垂直堆积的大而曲折的航道构成了现代潜艇扇的基本构件。近年来，三维高分辨率地震资料也揭示了陆坡上众多的小尺度地下曲流河道。最近的研究提供了新的见解，但也导致了强烈反对的观点，特别是关于弯曲通道中的螺旋流结构及其对通道形态的影响。通过采用精心设计的实验和数值模拟工作以及与参与海底形态研究的海洋地质学家密切合作的综合办法，可以清楚地了解海底航道的航道内和越岸过程。PI将进行实验室和数值模拟，主要集中在以下问题：(I)对海底航道弯道处水流分布的几何和入流限制；(Ii)螺旋流、推移质输运、断面变异性和海底航道迁移趋势之间的关系；(Iii)以及漫滩过程，包括由于弯道处水流分裂而产生的颗粒尺寸分布和叶的形成。实验将在一个12.2m×6.1m×1.5m的实验室水池中进行，并将使用密度和浑浊流的三维模型在实验室和现场尺度上进行数值模拟。更广泛的影响涉及为海底环境开发更好的地貌演变模型，这将有助于学术和行业研究人员对地震数据集的解释。除此之外，PIs概述了一项计划，通过资助南卡罗来纳大学已经实施的一个项目，增加少数群体参与地球科学研究的程度。他还计划举办一个研讨会。

Vertically aggrading large sinuous channels constitute the basic building blocks of modern submarine fans. In recent years, 3D high resolution seismic data have also revealed numerous small scale subsurface sinuous channels on continental slopes. Recent studies have contributed new insights, but have also led to strongly opposing views, specifically on the helical flow structure in sinuous channels and its effect on channel morphology. A clear picture of intra-channel and over-bank processes of submarine channels can emerge through a comprehensive approach involving carefully designed experimental and numerical modeling efforts and close collaboration with marine geologists involved in the study of seafloor morphology. The PI will pursue laboratory and numerical modeling with primary focus on the following issues: (i) geometric and inflow constraints on the flow distribution at submarine channel bends; (ii) relationships between helical flow, bed-load transport, cross sectional variability and migration tendency of submarine channels; (iii) and overbank processes including grain size distribution and lobe formation due to flow splitting at channel bends. Experiments will be conducted in a 12.2 m × 6.1 m × 1.5 m laboratory tank, and numerical simulations at both laboratory and field scales will be conducted using 3D models of density and turbidity currents. The broader impacts relate to developing better landscape evolution models for submarine environments that would aid interpretation of seismic data sets by both academic and industry researchers. In addition to this the PIs outline a plan to increase minority involvement in geoscience research through funding of a program that the University of South Carolina already has in place. He also plans to hold a workshop.