Petrological classification and lithology-specific abundance analysis of ice-rafted detritus (IRD) of sediment core GeoB18530-1

IRD-rich Heinrich Event (HE) layers are commonly used as stratigraphic markers of North Atlantic sediments. Gravity core GeoB18530-1, retrieved from the SE Grand Banks slope of Newfoundland, features a proximal and therefore complete and expanded HE layer succession, which was sampled and investigated in steps of 2.3 cm, permitting a petrographic, stratigraphic and statistical analysis of IRD lithology and abundance in unpreceded detail. In total, 8243 IRD particles of the > 1 mm fraction from 216 syringe samples were microscopically classified and counted following the newly developed IRD classification system of Bukar et al. (submitted) based on petrographic thin section analyses of selected larger IRD granules. […]

富含 IRD 的 Heinrich 事件 (HE) 层通常被用作北大西洋沉积物的地层标志。重力岩芯 GeoB18530-1，采集自纽芬兰东南大浅滩斜坡，具有近端且因此完整且扩展的 HE 层连续序列，该序列以 2.3 厘米的间隔进行采样和调查，从而实现了对 IRD 岩性的岩相学、地层学和统计分析，其细致程度前所未有。总计，从 216 个注射器样品中提取的 > 1 毫米的 8243 个 IRD 颗粒，按照 Bukar 等人（待发表）新近开发的 IRD 分类系统进行了显微镜下的分类和计数，该分类系统基于对选定的较大 IRD 粒的岩相学薄片分析。