Palaeooceanographic and palaeoglaciological data from gravity cores collected from the Northeast Greenland continental shelf (Outer Norske Trough), September 2016

Two gravity cores (PS100-144GC and PS100-146GC) were collected from the Norske Trough on the outer continental shelf of NE Greenland. The sediment cores were collected during cruise PS100 of the RV Polarstern to NE Greenland in 2016 to investigate the ice-ocean interactions of The Northeast Greenland Ice Stream (NEGIS) during early deglaciation (~21-10 ka BP). The following parameters were measured: GEOTEK Multi-Sensor Core Logger (MSCL, Durham University, DU); Shear Strength measurements (DU) foraminiferal faunal analysis (PS100-144GC only, DU) and stable isotopes (oxygen and carbon, measured at the NERC National Environmental Isotope Facility PS100-144GC only). This research was supported by the following grants: Alfred Wegener Institute (AWI) grant for ship time: AWI_PS100_01; NERC standard grant: NE/N011228/1; NERC National Environmental Isotope Facility grant: IP-1816-0618; NERC Radiocarbon Facility grant: NRCF010001, allocation no. 2113.0418

Gravity cores PS100-144GC and PS100-146GC were collected during cruise PS100 of the RV Polarstern in 2016 to the Northeast Greenland continental shelf. The cores were split lengthwise (3 sections for core PS100-144GC and 7 for PS100-146GC), photographed and described and shear strength measurements taken on board before being wrapped and stored at 4 degrees C. Each section of the core was x-rayed using a GEOTEK XCT scanner and passed through a GEOTEX Multi-Sensor Core Logger (MSCL, 7.9) at Durham University. The MSCL measured P-Wave velocity (m/s), gamma density (g/cc), magnetic susceptibility (SI x 10-5) and resistivity (Ohm.m) at a 1 cm resolution. Foraminiferal analysis: a sample volume of between 0.5 and 4 ml of sediment was soaked in deionised water for several hours then washed through 500 micrometre and 63 micrometre mesh sieves. The material retained on the 63 micrometre sieve was retained for foraminiferal analysis. Foraminifera were picked and counted from the wet residue under a binocular microscope immediately to reduce damage to agglutinated specimens and smaller, more fragile calcareous specimens. Foraminiferal stable isotope analysis: Oxygen (expressed as delta18O) and carbon (as delta13C) isotopic analyses were carried out separately on benthic and planktic foraminifera from both box core and gravity core. Approximately 20 specimens of the benthic species, Cassidulina neoteretis, and the planktic species Neogloboquadrina pachyderma were picked and measured where possible. Analyses were carried out using an IsoPrime mass spectrometer with a Multicarb preparation system at the Stable Isotope Facility in the British Geological Survey. Stable isotope results were calibrated to the VPDB scale of international standards with an analytical precision for both isotopes of > +/- 0.05 parts per thousand. Particle size analysis: Samples were prepared by removing organic material using 10% Hydrogen peroxide. Sodium hexametaphosphate was used to deflocculate the sediment, and samples were sieved through a 2 mm mesh sieve prior to putting through the laser scanner. This data was used to calculate the proportion of clay, silt, and sand-sized particles.

For the foraminiferal samples a target count of 300 individuals was set. This was not always possible, but the total specimens counted is quoted for all samples. Some samples were also barren. Stable isotope results were calibrated to the VPDB (Vienna Pee Dee Belemnite) scale of international standards with analytical precision for both isotopes of > +/- 0.05 percent. For particle size analysis, organic material was removed using Hydrogen peroxide and the samples were sieved through a 2mm sieve to remove coarser grains. 3 to 5 repeat measurement were taken for each sample to ensure consistent results were being produced.