High-resolution magnetostratigraphy of sediment cores from the Greenland Sea ...

High-resolution magnetostratigraphic analysis of three sediment cores from the base of the volcanic seamount Vesteris Banken in the Greenland Basin and one from the Jan Mayen Fracture Zone revealed records of three pronounced geomagnetic events: the Mono Lake excursion (28-27 ka), the Laschamp event...

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Bibliographic Details
Main Author: Nowaczyk, Norbert R
Format: Article in Journal/Newspaper
Language:English
Published: PANGAEA 1997
Subjects:
Online Access:https://dx.doi.org/10.1594/pangaea.730508
https://doi.pangaea.de/10.1594/PANGAEA.730508
Description
Summary:High-resolution magnetostratigraphic analysis of three sediment cores from the base of the volcanic seamount Vesteris Banken in the Greenland Basin and one from the Jan Mayen Fracture Zone revealed records of three pronounced geomagnetic events: the Mono Lake excursion (28-27 ka), the Laschamp event (37-33 ka) and the Biwa I/Jamaica event (189-179 ka). Rock magnetic investigations, measurements of magnetic susceptibility, and ARM and IRM acquisition/demagnetization experiments show that only fine-grained (titano) magnetite (<= 0.5 µm) is the dominant magnetic carrier mineral in the hemipelagic muds. There is no evidence for high amounts of high-coercivity minerals like haematite or goethite. Volcanic (basaltic) ash layers in sediments around Vesteris Banken seamount are characterized by extremely high values of magnetic susceptibility, reaching 16 000 times 10**-6 (SI), as well as by low median destructive fields of the anhysteretic remanent magnetization (MDFARM), indicating magnetite of larger grain ... : Supplement to: Nowaczyk, Norbert R (1997): High-resolution mangetostratigraphy of four sediment cores from the Greenland Sea - II. Rock magnetic and relative palaeointensity data. Geophysical Journal International, 131(2), 325-334 ...