Continental shelves in arid tropical settings present particular challenges to ²¹⁰Pb-based analysis of sedimentation rates and surface mixing owing to the combination of coarse sediment, deep and year-round bioturbation, and lower atmospheric flux of ²¹⁰Pb. The modern continental shelf at the northern terminus of the hyper-arid Gulf of Eilat/Aqaba (GOE) receives flood-runoff of siliciclastics, producing a mixed seabed with ~20% carbonate that is dominated by larger benthic foraminifera and mollusks. Focusing analysis on only the fine-fraction of deep-penetrating cores (≥70 cm) from 15 to 40 m water depths yields reliable ²¹⁰Pb profiles, in contrast to analysis of bulk sediment (graphical abstract). Sedimentation rates increase offshore five-fold, from 0.01–0.04 cm/y in 15 m water depth to 0.21–0.27 cm/y in 30–40 m depths, reflecting offshore redistribution of flood-delivered siliciclastic sediments away from the wadi mouth, a result also supported by an offshore increase in the inventory of excess ²¹⁰Pb. In contrast, the thickness of the surface mixed layer (SML) decreases from >30 cm to ~20 cm with proximity to anthropogenic stressors (channelized flood runoff, historic release of sewage and operation of fish cages), which we attribute to the suppression of macrobenthic burrowers. The rate of sedimentation on the Gulf shelf –away from dynamic bypassing in the 15 m shoreface – is comparable to other tropical carbonate shelves rich in large benthic foraminifera, and is higher than rates documented on the adjacent slope, increasing confidence in this approach to ²¹⁰Pb analysis using only the fine fraction. Analysis of the fine fraction rather than bulk sediment would be a useful adjustment to ²¹⁰Pb methodology in any area with scarce fine-grained sediment.

在干旱的热带地区，大陆架对²¹⁰ Pb的沉积速率和地表混合分析提出了特殊的挑战，这是由于沉积物较粗，生物扰动深而终，并且大气通量较低，仅为²¹⁰ Pb。高干旱的埃拉特/亚喀巴海湾（GOE）北端的现代大陆架接受硅质碎屑洪水，产生了含约20％碳酸盐的混合海床，主要由底栖有孔虫和软体动物主导。仅对15至40 m水深的深穿透岩心（≥70 cm）的精细分析进行重点分析，即可得出可靠的²¹⁰与大量沉积物分析（图形摘要）相反，Pb剖面。沉积速率增加了近五倍，从15 m水深处的0.01–0.04 cm / y增加到30–40 m深处的0.21–0.27 cm / y，反映出洪水输送的硅质碎屑沉积物从瓦迪河口向海上的重新分布，a海外库存量增加的结果也支持²¹⁰铅 相比之下，表面混合层（SML）的厚度从> 30 cm减小到〜20 cm，接近人为压力源（渠道化洪水径流，历史性污水排放和鱼笼操作），这归因于抑制大型底栖掘土机。海湾架子上的沉积速率（远离15 m沿岸的动态旁路）可与其他富含大型底栖有孔虫的热带碳酸盐架子相媲美，并且比相邻斜坡上记录的速率高，从而使该方法的可信度提高到²¹⁰铅分析仅使用细级分。在任何稀有细颗粒沉积物的地区，对细颗粒物而不是大量沉积物的分析都是对²¹⁰ Pb方法的有用调整。