Marine Isotope Stage 5e diatom assemblages in marine sediment core TPC287 (-60.31 degN, -36.65 degE, Cruise JR48)

• Main Authors: Chadwick, Matthew, Allen, Claire
• Format: Dataset
• Language: English
• Published: UK Polar Data Centre, Natural Environment Research Council, UK Research & Innovation 2021
• Subjects: "EARTH SCIENCE","BIOLOGICAL CLASSIFICATION","PROTISTS","DIATOMS"; Diatoms; Interglacial; Sediment core; Southern Ocean; Olympus; Chadwick
• Online Access: https://dx.doi.org/10.5285/f8f7bbf7-bd86-45e5-bf22-f7fc327c94bf; https://data.bas.ac.uk/full-record.php?id=GB/NERC/BAS/PDC/01450

This dataset presents the relative diatom abundances of 55 species/groups from the 132-120 ka interval in marine sediment core TPC287 (-60.31 degN, -36.65 degE). This age interval corresponds to the peak of Marine Isotope Stage 5e (130- 116 ka). Microscope slides were prepared using a method adapted from Scherer (1994) and 300+ diatom valves were counted for each depth sample to produce the relative percentage abundance of each diatom species/group. This project was funded by the UK Natural Environment Research Council Grant NE/L002531/1 : Sediment core material was collected on Cruise JR48 (2000) of the RRS James Clark Ross (https://www.bodc.ac.uk/resources/inventories/cruise_inventory/reports/jr48.pdf). For the diatom assemblage data, microscope slides were produced using a method adapted from Scherer (1994). Samples of 7-20 mg were exposed to 10% Hydrochloric acid to remove any carbonate, 30% Hydrogen peroxide to break down organic material and a 4% Sodium Hexametaphosphate solution to promote disaggregation and placed in warm water bath for minimum 12 hours. The material was homogenised into a ~10cm water column and allowed to settle randomly onto coverslips over a minimum of 4 hours. The water was drained away and coverslips were mounted on microscope slides with Norland Optical Adhesive (NOA 61). Slides were investigated with a light microscope (Olympus BH-2 at x1000 magnification) and a minimum of 300 diatom valves were counted for each sample. Age Model Chadwick et al. (submitted) align core TPC287 to the EDC3 chronology by correlating the sediment core magnetic susceptibility to the magnetic susceptibility for TPC288 (Pugh et al. 2009). Translation between the EDC3 and LR04 chronologies uses the conversion tables in Parrenin et al. (2013). : Instrumentation; Trigger corer, Piston corer, Diatom settling tanks and bench, Olympus BH-2 light microscope. : All diatom abundance values have an error of ±0.16 %. Ages for samples have a chronological uncertainty of ~2 ka. Sediment samples have a depth resolution of 2 cm and age resolution of 0.5-1.2 ka.