Transport of continental shelf sediments to the deep ocean can be studied from displaced symbiont-bearing larger benthic foraminifera found in turbidity current deposits. The larger benthic foraminifera habitat depth, physical characteristics and preservation serve as indicators for understanding sediment transport dynamics near the seabed and in the water column. Here, an experiment was designed to explore sediment transport in a closed flume system using simulated high current velocities. Shelf sediments from the Gulf of Eilat/Aqaba, dominated by Amphistegina papillosa and Operculina ammonoides, were subjected to 60 cm s⁻¹ and 80 cm s⁻¹ current velocities while collected in a 10 cm vertical sediment trap. Larger benthic foraminifera abundance, shell physical properties and preservation were analyzed and compared with the original bulk sediments. The experiment results showed that at 80 cm s⁻¹ velocity, larger benthic foraminifera shells of all sizes and preservations are efficiently resuspended and transported in large quantities throughout the water column, as opposed to their transport as bedload by the lower velocity current. Larger benthic foraminifera shape also has a role in the transport distances and accumulation depths. Operculina ammonoides shells were found to be more portable, compared to Amphistegina papillosa, due to their flatter discoid shape. The results suggest that a threshold velocity of ca 80 cm s⁻¹ was needed to generate the thick coarse deposits found in the Gulf of Eilat/Aqaba slope sedimentary record, which were previously suggested to be triggered by large magnitude seismic events. Lower velocities probably winnowed minor amounts of larger benthic foraminifera shells (with little or no coarser sediments) that were deposited as a thin sand layer may point to lower magnitude seismic triggers. In conclusion, larger benthic foraminifera shells are transported and deposited in accordance with their hydrodynamic properties, resulting in assemblage differentiation along the transport pathway. This study shows that the fossil biogenic composition in slope sediments includes valuable information on current velocities, transport dynamics and possible triggers in the geological record.

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顺其自然：从有孔虫的角度对泥沙输送的实验模拟

大陆架沉积物向深海的运输可以通过在浊流沉积物中发现的带有共生体的大型底栖有孔虫进行研究。较大的底栖有孔虫栖息地深度、物理特征和保存情况可作为了解海床附近和水柱中沉积物迁移动态的指标。在这里，设计了一个实验，以使用模拟的高流速探索封闭水槽系统中的沉积物输送。来自埃拉特湾/亚喀巴湾的陆架沉积物，主要是Amphistegina papillosa和Operculina ammonoides，受到 60 cm s ^-1和 80 cm s ^-1的影响收集在 10 厘米垂直沉积物陷阱中时的当前速度。对较大的底栖有孔虫丰度、贝壳物理性质和保存情况进行了分析，并与原始大块沉积物进行了比较。实验结果表明，在 80 cm s ^-1速度下，各种尺寸和保存物的较大底栖有孔虫贝壳被有效地重新悬浮并在整个水体中大量运输，而不是通过较低速度电流作为床载运输。较大的底栖有孔虫形状对运输距离和积累深度也有影响。与Amphistegina papillosa相比，发现Operculina ammonoides壳更便于携带，由于它们更平坦的盘状形状。结果表明，阈值速度约为80 cm s ^-1需要生成在埃拉特湾/亚喀巴斜坡沉积记录中发现的厚厚的粗矿床，以前认为这些矿床是由大地震事件触发的。较低的速度可能将少量较大的底栖有孔虫贝壳（很少或没有较粗的沉积物）作为薄沙层沉积，这可能指向较低震级的地震触发。总之，较大的底栖有孔虫壳根据其水动力特性进行运输和沉积，导致沿运输途径的组合分化。这项研究表明，斜坡沉积物中的化石生物成分包括地质记录中有关当前速度、传输动力学和可能触发因素的有价值信息。