Correspondence analysis (CA) and statistical diversity analysis were carried out on the palynological dataset (total counts per gram) to confirm assemblage designations (Figs. 4 and 5), to identify any disturbance to the core prior to interpretation, and to estimate diversity (Fig. 6). Dinoflagellate cyst assemblages (DA1–DA5) and pollen assemblages (PA1–PA4) were defined by visually comparing changes in the species dominance (Figs. 7 and 8), and confirmed by CA (Fig. 4) using the first three axes (describing the highest percentages of variance). Five samples from below the CIE at 2619.60, 2617.35, 2617.44, 2614.73, and 2614.71 m (indicated in Fig. 5) contain Apectodinium, in contrast to the other samples below the CIE (Figs. 3 and 7). Some of these samples (2619.60, 2614.73, and 2614.71 m) also contain negative δ13CTOC, indicative of the CIE (Fig. 3). To test if coincident pollen and spore changes also occur in these samples, we used CA on the pollen and spore data only (Fig. 5a). PA1–PA4 (symbols) plot in clusters, signifying their palynological similarity. The species most associated with an assemblage are clustered with the samples from that assemblage. For example, Inaperturopollenites hiatus and bisaccate pollen (highly abundant before the CIE, Fig. 8) are high on axis 1 where the earlier samples from PA1 and PA2 occur, and Caryapollenites spp. and fungal spores (abundant after the CIE, Fig. 8) are low on axis 1 near the younger samples from PA4. The two samples 2619.60 and 2614.71 have a spore and pollen palynological signature similar to samples from PA3/4 during the CIE (plot lower on axis 1) and are either not in the correct location (it cannot be discounted that these samples represent tectonically emplaced younger material (Payne et al., 2005), or were misplaced during drilling operations core handling), or represent very short episodes of both marine and terrestrial ecologic change to CIE-type conditions. The rapid and transient nature of these two shifts appears to suggest that the latter explanation may be unlikely, and we have therefore shaded samples from these two depths in Figs. 3, 6–9.
samples
Five
samples
2619.60, 2617.35, 2617.44, 2614.73, and 2614.71 m
m
samples
2619.60, 2614.73, and 2614.71 m
m
samples
two
samples
2619.60 and 2614.71