Abstract Research on sediment drifts (the non-genetic term for contourites) is becoming increasingly popular due to their economic potential and usefulness as records of past climate and bottom water circulation changes. We examine the geographical extent of a sediment drift at the Cipero Formation, Trinidad (Cipero-1 site) using benthic foraminifera to measure (1) winnowing, based on the statistical similarity of replicate >63 and >106 μm samples, (2) bottom current action using the abundance of Planulina wuellerstorfi, and (3) down-slope transport, based on the occurrence of allochthonous shallower-water species. We compare this previously published data with new benthic foraminiferal data collected at two other locations (Cipero-2 and Cipero-3 sites). All three exposures consist of cream marls and were laid down at ≥2000 m palaeodepths during the Middle Miocene. We confirm the Cipero-1 exposure was a sediment drift based on an enhanced bottom current that traveled parallel to the palaeo-slope, good sorting, and no shallower-water foraminifera. The Cipero-2 and Cipero-3 sites were not sediment drifts. Both sites experienced sluggish bottom water circulation but were palaeoenvironmentally dissimilar. The Cipero-2 samples were not winnowed and experienced down-slope transport, indicated by Cibicidoides compressa, Cibicidoides crebbsi, and Triloculina trigonula. We present the first model showing possible influences of coastal upwelling at the Cipero Formation. Our Cipero-3 site experienced a possible episodic impulse of phytodetritus based on increased abundances of Siphonodosaria pomuligera and Globocassidulina subglobosa. Palaeoenvironmental proxies showed the Cipero Basin as generally cold, nutrient deficient and high oxic, reflective of the proto-North Atlantic Deep Water.

中文翻译：

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底栖有孔虫作为探索加勒比东南部特立尼达 Cipero 组沉积物漂移地理范围的工具

摘要 由于沉积物漂移（等高岩的非遗传术语）作为过去气候和底部水循环变化的记录，其经济潜力和实用性，因此对沉积物漂移（等高岩的非遗传术语）的研究越来越受欢迎。我们使用底栖有孔虫来测量 (1) 风选，基于重复 >63 和 >106 μm 样本的统计相似性，(2) 底部当前的行动利用 Planulina wuellerstorfi 的丰度，以及 (3) 下坡运输，基于外来浅水物种的出现。我们将之前发布的数据与在其他两个地点（Cipero-2 和 Cipero-3 站点）收集的新底栖有孔虫数据进行比较。所有三个暴露点都由奶油色泥灰岩组成，并且在中中新世沉积于≥2000 m 的古深度。我们确认 Cipero-1 暴露是基于增强的底流的沉积物漂移，该流平行于古斜坡，良好的分类，没有浅水有孔虫。Cipero-2 和 Cipero-3 站点不是沉积物漂移。两个地点都经历了缓慢的底部水循环，但古环境不同。Cipero-2 样品未经风选并经历了下坡运输，如 Cibicidoides compressa、Cibicidoides crebbsi 和 Triloculina trigonula 所示。我们展示了第一个模型，显示了 Cipero 组沿海上升流的可能影响。基于 Siphonodosaria pomuligera 和 Globocassidulina subglobosa 丰度的增加，我们的 Cipero-3 站点经历了可能的植物碎屑脉冲。古环境代理显示西佩罗盆地普遍寒冷、营养缺乏和高氧，反映了原始北大西洋深水。