Foraminifera occurrences of IODP Hole 386-M0090D

Results of Foraminifera assemblage analyses from the above given hole of International Ocean Discovery Program (IODP) Expedition 386 (Japan Trench Paleoseismology). The offshore phase of this expedition took place between 2021-04-13 and 2021-06-01 onboard Japanese R/V Kaimei from and to Yokosuka, Japan, followed by an onshore phase onboard D/V Chikyu between 2022-02-14 – 2022-03-15. During the offshore phase, micropaleontology samples were taken from the end of split cores at 5 m intervals. During the onshore phase approximately 2 cubic centimetres of sediment from each of these samples were analysed for foraminifera. After drying overnight in a ~40°C oven, samples were disaggregated in a solution of deionized water, Calgon, and H2O2 to ensure removal of clay-sized particles. Samples were then wet sieved through a 63 μm mesh sieve and rinsed with deionized water. The coarse fraction was placed on filter paper in an oven at ~40°C until it dried completely. Faunal identifications were made using a Meiji Techno RZ binocular light microscope. Taxonomic composition, abundance, and preservation state were observed in the >63 μm size fraction.

国际海洋发现计划（International Ocean Discovery Program, IODP）第386航次（日本海沟古地震学）上述钻孔的有孔虫组合分析结果。该航次的海上阶段于2021年4月13日至2021年6月1日在日本“海洋”号科考船（R/V Kaimei）上开展，往返于日本横须贺；随后的陆上阶段于2022年2月14日至2022年3月15日在“地球”号钻探船（D/V Chikyu）上进行。海上阶段期间，每隔5米从劈分岩芯末端采集微体古生物学样品。陆上阶段期间，从每个样品中取约2立方厘米沉积物进行有孔虫分析。样品在约40°C烘箱中过夜干燥后，置于去离子水、Calgon和H2O2的混合溶液中分散，以确保去除黏土粒径的颗粒。随后将样品通过63μm网目筛进行湿筛，并用去离子水冲洗。粗颗粒部分置于滤纸上，在约40°C烘箱中干燥至完全。使用明治Techno RZ双目光学显微镜进行动物群鉴定。在>63μm粒级部分中观察分类组成、丰度和保存状态。