Investigation of Miocene foraminifera in sediment core CRP-1 from the Ross Sea, Antarctica

A faunal comprising 18 foraminiferal taxa wa recovered from a suite of 52 core samples from lower Miocene sandstone, claystone and diamictite in the CRP-1 drillhole, Cape Roberts, Antarctica. The fauna is characterised by low foraminiferal abundance and diversity, the absence of planktics, and typically, the presence of Cribroelphidium sp. and/or Melonis spp. These factors indicate deposition in an inner shelf or nearshore environment. Many of the foraminifers found in CRP-1 also occure in the upper Oligocene-Miocene sequences in CIROS-1 and DSDP-270, but the fauna provides no precise indication of age. Typical and distinctive species from CRP-1 are illustrated with SEM photomicrographs.

从南极罗伯茨角CRP-1钻孔的下中新统砂岩、泥岩及混积岩（diamictite）地层的52个岩心样品组合中，采集到由18个有孔虫分类单元（foraminiferal taxa）构成的有孔虫动物群。该动物群具有有孔虫丰度与多样性偏低、无浮游有孔虫的特征，且通常可见筛立虫属（Cribroelphidium）未定种和/或Melonis属多个种。上述特征指示其沉积环境为内陆架或近岸环境。CRP-1钻孔中发现的多数有孔虫类群，同样产出于CIROS-1与DSDP-270的渐新统上部-中新统地层序列中，但该动物群无法提供精确的年代依据。本次研究借助扫描电子显微镜（Scanning Electron Microscope, SEM）显微照片，对CRP-1钻孔中的典型及特征有孔虫物种进行了图示展示。