Following the termination of the Messinian salinity crisis ~5.3 million years ago, massive sedimentation in the Eastern Mediterranean Sea formed the huge Nile Delta. Alongside delta propagation, a continental shelf was accreted along the Levant margin. For several decades it was assumed that these two sedimentary structures were closely connected. Levant shelf deposits are composed of Nile-derived sediments and present-day measurements show that sand is currently being transported alongshore from the Nile Delta to offshore Israel. This study reexamines the existing paradigm about sediment transport and shelf-delta connection. We show that longshore sand transport is just a small part of a much larger process termed here margin-parallel sediment transport (MPST). Sand is transported in a nearshore shallow-water belt where marine currents are highly energetic. At the same time, shale is transported at greater depths over the deeper shelf and the continental slope where marine currents are weaker. To model the accretion of the Levant shelf alongside the Nile Delta we use a 3D, diffusion-based, stratigraphic modeling tool (DionisosFlow) with a new module representing MPST. Our results show that margin-parallel transport of silt and clay in the deeper waters accounts for the bulk of deposition offshore Israel and is responsible for the development of the Levant shelf. Moreover, though MPST has begun coevally with delta formation, massive accretion of the Levant shelf was delayed by 2–3 My. Initially, a continental shelf formed offshore Sinai, then offshore Israel, and most recently along the Lebanon coast. Our model also demonstrates the significant lithological differences observed between sedimentation in front of the Nile River mouth and along adjacent continental margin. High energy down-slope sediment transport carries sand, silt, and clay, whereas margin-parallel currents are relatively weak and carry mainly silt and clay. One exception within the margin-parallel system is the highly energetic nearshore current that transports sand. Thus, we point out, MPST is an efficient separator between shale and sand.

在大约530万年前的麦西尼亚盐度危机终结之后，东地中海的大规模沉积形成了巨大的尼罗河三角洲。除三角洲传播外，沿黎凡特边缘还增加了大陆架。几十年来，人们一直认为这两个沉积结构是紧密相连的。黎凡特陆架沉积物由源自尼罗河的沉积物组成，目前的测量结果表明，目前有沙子从尼罗河三角洲沿岸运输到以色列近海。这项研究重新审查了有关泥沙输送和陆架-三角洲连接的现有范例。我们表明，沿岸的沙土运输只是一个更大的过程的一小部分，在这里称为边际平行沉积物运输（MPST）。沙子在近海浅水带运输，那里的海流高度活跃。同时，页岩在海流较弱的较深的陆架和大陆坡上以更大的深度运输。为了对黎凡特陆架的堆积物和尼罗河三角洲进行建模，我们使用了基于3D，基于扩散的地层建模工具（DionisosFlow），其中包含一个表示MPST的新模块。我们的结果表明，在较深水域中，淤泥和粘土的边际平行运输占以色列近海沉积物的大部分，并为黎凡特陆架的发展负责。此外，尽管MPST已开始逐渐形成三角洲，但黎凡特大陆架的大量积聚被延迟了2-3 My。最初，一个大陆架在西奈半岛的海上形成，然后在以色列海上形成，最近在黎巴嫩沿岸形成。我们的模型还证明了尼罗河河口前方和邻近大陆边缘的沉积之间存在明显的岩性差异。高能下坡沉积物输送带沙，粉砂和黏土，而边际平行流相对较弱，主要带粉砂和黏土。平行边际系统中的一个例外是高能量的近岸海流，用于输送沙子。因此，我们指出，MPST是页岩和沙子之间的有效分离器。平行边际系统中的一个例外是高能量的近岸海流，用于输送沙子。因此，我们指出，MPST是页岩和沙子之间的有效分离器。平行边际系统中的一个例外是高能量的近岸海流，用于输送沙子。因此，我们指出，MPST是页岩和沙子之间的有效分离器。