Data Publication

Data from redeposition experiments of glacial Black Sea sediments

Nowaczyk, Norbert R.

GFZ Data Services

(2020)

This data publication includes detrital remanent magnetisation data of glacial sediments from the Arkhangelsky Ridge in the SE Black Sea. In order to test the acquisition of a detrital remanent magnetization (DRM) in glacial Black Sea sediments material from ca. 800 ml of diluted mud with a density of 1.3 gcm-3 was successively redeposited into seven plastic boxes under controlled magnetic field conditions. A two-component coil system was used to adjust the magnetic field in horizontal (H, equal to magnetic NS) and vertical (V) direction. Total field strength for each experiment with seven samples was varied between 1.72 and 114.21 µT (1st column of data sheet), mostly opposite to the ambient field in the laboratory. Compaction (partial drying) of the diluted mud was accomplished by evaporation of a fraction of the pore water. Sample boxes were sited on a wooden platform. Vibration of the platform, excited by an old computer fan with an imbalance hanging below the platform, was intended both to promote alignment of magnetic particles parallel to the field set by the coils and to force settling of the sediments during partial drying. The majority of the samples were treated this way, entry ‘vibr.’ in column ‘action’ of data sheet. A smaller portion of the samples were created on ‘still’ platform, that is, without vibration. Samples were treated the following way: Measurements of low-field magnetic susceptibility (k-bulk) were performed with an AGICO MFK-1S susceptibility meter. Measurements of the detritral remanent magnetization (DRM) and of the anhysteretic remanent magnetization (ARM) were performed with a 2G 755 SRM long-core cryogenic magnetometer. The ARM was imparted with a 2G660 single-axis alternating field (AF) demagnetizer using 100 mT alternating field and 50 µT static field. After ARM measurements, samples produced on vibrating platform also were imparted a ‘strong’ ARM (sARM) using 100 mT alternating field and 150 µT static field. DRM and (s)ARM both were stepwise demagnetized with the in-line 3-axes AF demagnetizer of the cryogenic magnetometer, applying steps of 0, 5, 10, 15, 20, 30, 40, 50, 65, 80, 100 mT AF peak amplitude. Iso-thermal remanent magnetizations (IRM) were imparted with a 2G 660 pulse magnetizer using 1500 mT for producing a saturation magnetization and -200 mT for remagnetization of the low-coercive fraction. Measurements were performed with a Molyneux spinner magnetometer. The data are provided as ASCII table and are described in Nowaczyk et al. (2020) and the associated data description file.

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