High-resolution sediment record from a submarine meandering canyon system in the eastern Atlantic

Based on a high-resolution sediment record from a submarine meandering canyon system offshore the present-day hyperarid Saharan Africa, two phases of turbidity-current activity can be distinguished during the past 13,000 years. Frequent, siliciclastic turbidity currents can be related to deglacial sea-level history, whereas rhythmically recurring fine-grained and carbonate-rich turbidity currents with recurrence times of roughly 900 years are inferred for the Holocene. Various trigger mechanisms can be considered to initiate turbidity currents, but only a few can explain a periodic turbidite activity. A comparison of Holocene turbidite recurrence times and basic cycles of 900 and 1,800 years found in various Holocene paleoclimate studies suggests that a previously unrecognized climate-related coupling may be active.

基于现今极度干旱的撒哈拉非洲沿岸海底蜿蜒峡谷系统的高分辨率沉积记录，过去13,000年间可以区分出两个浊流活动的阶段。频繁的硅质碎屑浊流与冰后期海平面变化历史相关联，而大约900年周期性循环出现的细粒和富含碳酸盐的浊流则可推断为全新世时期的特征。尽管考虑了多种触发浊流的机制，但仅有少数能够解释周期性的浊流沉积活动。通过对全新世浊流沉积循环时间与多种全新世古气候研究中发现的900年和1,800年基本周期进行比较，推测可能存在一种先前未被识别的气候相关耦合机制正在发挥作用。