The benthic foraminiferal record of Late Quaternary glacial/ interglacial cycles in core E 36-23, East Tasman Plateau

To reconstruct the paleoceanographic history of intermediate and bottom water masses one piston core and six surface samples were examined. Core E 36-23 is located at the East Tasman Plateau from 2521 m waterdepth. With a sampling interval from 3 to 10 cm, 63 sediment samples over the entire corelength (550 cm) were examined for the benthic foraminiferal content (> 125 μm). In all 5 2 species were identified, 13 form the dominant group with percentages of minimum 10% of the whole fauna at least once. The surface sample locations are widely distributed in the Tasman and the southern Coral Sea representing various bottom water regimes. The benthic foraminiferal content was identified and counted and revealed individual associations. The species distribution and characteristic associations (epi/infaunal and arenaceous species) were used as basis for paleoceanographic and stratigraphic interpretations. The results of a correspondence analysis of the raw data support the interpretation of a cold/warm cyclicity in the sedimentational history of the core. As representative assemblages for modem ecological conditions the different surface associations have been compared with associations down the core by correlation factor analysis. The results of these analyses allow the establishment of a preliminary stratigraphic frame appropriate to a time frame which covers the last420.000years (δ 18 O stage 12) approximately. The mean sedimentation rate is estimated at 1.2 cm/ky. The correlation factors indicate that core E 36-23 was apparently influenced by Deep Water at a core depth of 190 cm. At core depths 50-120 cm and 200-450 cm, faunal analyses indicate an influence of Antarctic Intermediate Water.