XRF down-core scanning data, benthic oxygen isotope, sand fraction and geochemistry data of sediment cores from the subarctic Northwest Pacific during the last 500,000 years

• Published in: Frontiers in Marine Science
• Main Authors: Chao, Weng-si, Jacobi, Lara, Niederbockstruck, Bryan, Kuhn, Gerhard, Nürnberg, Dirk, Tiedemann, Ralf, Lembke-Jene, Lester
• Format: Other/Unknown Material
• Language: English
• Published: PANGAEA
• Subjects: alkenone concentration; AWI_Paleo; benthic oxygen isotope; Carbonate; Northwest Pacific; Paleoenvironmental Reconstructions from Marine Sediments @ AWI; productivity; XRF data; Pacific; Hess; Fid; Emperor Seamount Chain; Subarctic
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.955877

A meridional transect of deep sea sediment cores from the subarctic Northwest Pacific were retrieved from the Emperor Seamount Chain and Hess Rise during cruises SO202 in 2009 and SO264 in 2018. XRF scanning, benthic oxygen isotope, carbonate (CaCO3) content and accumulation rates, sand fraction (>63 µm) and alkenone concentration were measured, in order to reconstruct changes in the export production and its relation to carbonate deposition and dissolution on suborbital timescales for the last 500,000 years before present. All measurements were done at the AWI in Bremerhaven. The XRF-scanning measurements were carried out with an Avaatech XRF core scanner. The X-ray excitation scanning settings were 10 kV at 150 mA with no filter for a count time of 10 s, and a rhodium target X-ray tube was deployed. The sample distance was 10 mm, with a 10x12 mm slit size. Sediment samples were freeze-dried and washed through a 63-µm sieve. The coarse fractions (>63 µm) were dried in an oven at 50°C and dry sieved into four different size fractions. Benthic oxygen isotopes were measured on a Thermo Finnigan MAT 253 isotope ratio mass-spectrometer coupled to an automated KIEL IV CARBO preparation device. The CaCO3 content was calculated from TC and TOC which were measured by a CNS-analyzer (Elementar vario EL III) and a carbon/sulfur analyzer (Eltra CS-800). Alkenones were analyzed by GC (HP-6891) fitted with a flame ionization detector (GC-FID) using Helium as carrier gas (1.5 ml min 1 constant flow).