Submarine channel flow processes and deposits: A process-product perspective
Submarine channel flow processes and deposits: A process-product perspective
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DOI：
10.1016/j.geomorph.2015.03.005
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发表时间：
2015-09
期刊：
影响因子：
3.9
通讯作者：
J. Peakall;E. Sumner
中科院分区：
文献类型：
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作者：
J. Peakall;E. Sumner
在过去的几十年里，过程-产物研究一直是过程沉积学发展的核心，它能够首先测量流量，然后检查产生的沉积物，消除了与先前解释相关的许多模糊性。然而，对于地球上的大型地貌系统来说，可能是独一无二的，没有对海底通道进行实地规模的过程产物研究。事实上，由于测量这些强大的、不常见的、通常难以接近的流动的困难，甚至对流动动力学的直接测量也非常少。在过去的十年中，物理实验为模型海底通道系统提供了第一个过程-产物研究，使我们能够将流动行为和沉积模式联系起来。数值模拟，特别是海底通道流动动力学的数值模拟补充了这一点。在这里，我们首次综合了这些观测结果，在我们对海底通道的直接了解的背景下，得出了海底通道流动动力学的概述，以及低纬度和高纬度系统的面向过程的通道内结构模型。此外，我们还提出了点坝发育和演化的新模式，以及由细粒斜增积矿床覆盖的点坝组成的内弯沉积聚集。这项工作揭示了海底通道中丰富的流动行为和相关的沉积模式，它们比河流系统要复杂得多。
Process-product studies have been central to the development of process sedimentology over the past few decades, with the ability to first measure flows, and then examine the resulting deposits, removing much of the ambiguity associated with previous interpretations. However, perhaps uniquely for large geomorphic systems on Earth, there are no field-scale process-product studies of submarine channels. In fact, there are remarkably few direct measurements even of the flow dynamics as a result of the difficulties of measuring these powerful, infrequent, and often inaccessible flows. Over the past decade, physical experimentation has provided the first process-product studies for model submarine channel systems, enabling us to link flow behaviour and sedimentation patterns. This has been supplemented by numerical simulations, particularly of submarine channel flow dynamics. Here for the first time, we synthesise these observations, in the context of our direct knowledge of submarine channels, to derive an overview of submarine channel flow dynamics, and process-orientated intra-channel architecture models for low and high latitude systems. In addition, we propose new models for the development and evolution of point bars and for inner bend sedimentary accumulations that can comprise point bars overlain by finer-grained oblique accretion deposits. The work reveals a rich range of flow behaviour and associated sedimentation patterns in submarine channels that are far more complex than in fluvial systems.