Late Pliocene dinoflagellate cyst and diatom analysis from a high resolution sequence in DSDP Site 594, Chatham Rise, south west Pacific

A high resolution mixed carbonate and siliciclastic sequence from DSDP Site 594 contains a detailed record of climate change in the late Pliocene. The sequence can be accurately dated by the LAD of Nitzschia weaveri, the LAD of Thalassiosira insigna. the LAD of T. vulnifica and the LAD of T. kolbei diatom datums. Carbonate content and delta (18) signatures provide added re solution and place the sequence between isotope stages 100 and 9. The sequence contains well-preserved and diverse dinoflagellate cyst floras . Use of principal component (PCA) and canonical correspondence analyses (C CA) identifies changes in the assemblages that principally reflect warming and cooling trends. Species associated with warmer climates included Impagi dinium patulum, I. paradoxum and I sp. cf. paradoxum while those from coole r climates include Invertecysta tabulata and I. velorum. CCA is shown to be a valuable method of determining the past environmental preferences of ext inct species such as I. tabulata. (C) 2001 Elsevier Science B.V. All rights reserved.