| Summary: | Abundance records of planktonic foraminifera (>150fun) from the upper 60 - 80 cm of two marine sediment cores, CAR-MON 2 and CAR-MON 4, have been analysed in order to investigate the late Pleistocene climatic and oceanic history of the area around Montserrat. CAR-MON 2 and CAR-MON 4 were collected from around the south of the island by the "Carval" cruise of the R. V. L'Atlante in 2002. The cores were sampled at 5 cm intervals, with samples dating from the last glacial maximimi to recent. Seven planktonic taxonomic groups dominate the faunal assemblage in CARMON 2: G. ruber (white) (24.5%), G. ruber (pink) (12.7%), A^. pachyderma (d) (12.5%), G. sacculifer (12.0%), G. sacculifer (ext.) (6.5%), and G. aequilateralis (6.3%) and G. glutinata (4.9%). CAR-MON 4 is dominated by: G. ruber (white) (32.8%), G. ruber (pink) (12.7%), G. sacculifer (11.9%), G. glutinata (8.0%), andiV. pachyderma (d) (6.2%), G. sacculifer (ext.) (3.9), and G. bulloides (3.8%). The combination of dominant species suggests well mixed waters have surrounded ttie island throughout much of the late Plesistocene, especially the last 12 ka. Based on the paleoecological significance of planktonic foraminiferal abundance fluctuations, a signal of climate and ocean variability is observed throughout the late Pleistocene. There is faunal evidence showing generally warmer sea surface temperature (SST) during the interglacial Oxygen Isotope Stage 1 (OIS 1), and cooler SST during the glacial OIS 2 period. Overlaid on this is evidence of a cool period at the very beginning and end of OIS 1, with warm SST in between. A particularly cool period occurred towards the end of OIS 2, followed by a warmer period at the OIS 2/OIS 3 boundary (18-20 ka). There is faunal evidence suggesting CAR-MON 4 (located closer to Montserrat) is in an area of more intense upwelling and productivity than CAR-MON 2. Productivity and upwelling were shown to be greater during OIS 1 than OIS 2, with intensification occurring at the start and towards the end of OIS 1, and a peak in productivity occurring in late OIS 2 (18 - 20 ka). Analysing planktonic Fragmentation Index (PFI) values and benthic foraminifera abundances show low levels of preservation and high levels of dissolution during most of OIS 1, and high levels of preservation and low levels of dissolution during most of OIS 2. Dissolution and productivity in the area around Montserrat were particularly high at the start and middle of OIS 1, and at the end of OIS 2, and particularly low at a third way through OIS 1, and just after the OIS 1/OIS 2 boundary (c. 12 ka). Faculty of Science
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