Rock magnetic, geochemical and sedimentological properties related to IRD composition and content of sediment core GeoB18530-1

The IRD-rich Heinrich Event (HE) layers of gravity core GeoB18530-1, retrieved from the SE Grand Banks slope of Newfoundland, coincide with bulk magnetic susceptibility maxima. This positive correlation of IRD content and susceptibility is widely observed and at first glance contradictive, since det...

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Bibliographic Details
Main Authors: von Dobeneck, Tilo, Bukar, Shettima
Format: Other/Unknown Material
Language:English
Published: PANGAEA
Subjects:
Online Access:https://doi.pangaea.de/10.1594/PANGAEA.971785
Description
Summary:The IRD-rich Heinrich Event (HE) layers of gravity core GeoB18530-1, retrieved from the SE Grand Banks slope of Newfoundland, coincide with bulk magnetic susceptibility maxima. This positive correlation of IRD content and susceptibility is widely observed and at first glance contradictive, since detrital dolomite, the most common IRD component, is weakly magnetic and should therefore reduce rather than enhance bulk magnetic susceptibility. As Part I of the associated manuscripts (Bukar et al., submitted) showed, the petrology of HLs is rather diverse; some prominent magmatic and metamorphic IRD species should actually have relatively high magnetic susceptibilities. This data set bundle comprises a collection of bulk rock magnetic, geochemical and sedimentological sediment records revealing the influence of specific magnetic mineral fractions, IRD lithologies and textural properties on the magnetic susceptibility signal. Part II of the associated manuscripts (Bukar et al., submitted) also features so far unreported rock magnetic property data of all observed IRD lithologies. These susceptibility, IRM, ARM and HIRM data were acquired from large or pooled (granule to gravel size) classified IRD specimens. Since IRD particles are not limited to larger grain sizes, three composite bulk sediment samples from units H1, I1 and H2 were wet-sieved to reveal the grain-size dependence of magnetic susceptibility. Six linear regression models finally compare the predictability of magnetic susceptibility from rock magnetic, geochemical, sedimentological and petrological data.