IMIS | Flanders Marine Institute
 

Flanders Marine Institute

Platform for marine research

IMIS

Publications | Institutes | Persons | Datasets | Projects | Maps
[ report an error in this record ]basket (0): add | show Printer-friendly version

Magnetic susceptibility as a high-resolution correlation tool and as a climatic proxy in Paleozoic rocks - Merits and pitfalls: Examples from the Devonian in Belgium
Da Silva, A.-C.; De Vleeschouwer, D.; Boulvain, F.; Claeys, P.; Fagel, N.; Humblet, M.; Mabille, C.; Michel, J.; Sardar Abadi, M.; Pas, D.; Dekkers, M.J. (2013). Magnetic susceptibility as a high-resolution correlation tool and as a climatic proxy in Paleozoic rocks - Merits and pitfalls: Examples from the Devonian in Belgium. Mar. Pet. Geol. 46: 173-189. dx.doi.org/10.1016/j.marpetgeo.2013.06.012
In: Marine and Petroleum Geology. Elsevier: Guildford. ISSN 0264-8172, more
Peer reviewed article  

Available in  Authors 
    VLIZ: Open Repository 279381 [ OMA ]

Author keywords
    Magnetic susceptibility; Paleozoic; Paleoenvironment; Paleoclimate;Diagenesis; Magnetic minerals; Orbital forcing

Authors  Top 
  • Da Silva, A.-C., more
  • De Vleeschouwer, D., more
  • Boulvain, F., more
  • Claeys, P., more
  • Fagel, N., more
  • Humblet, M.
  • Mabille, C.
  • Michel, J., more
  • Sardar Abadi, M., more
  • Pas, D., more
  • Dekkers, M.J.

Abstract
    Low-field magnetic susceptibility (?in) measurements are quick and sensitive enabling the creation of high-resolution records; making ?in an attractive correlation tool and a proxy for paleoclimate and paleoenvironments. In geologically young material – foremost in Cenozoic sediments – ?in belongs to the geoscientist's toolkit. However, ?in is a convolved signal and may reflect other processes than the often implicitly inferred depositional conditions. Diagenesis, remagnetization and low-grade metamorphism, can potentially obscure the original, depositional, ?in signal. This aspect is particularly important when interpreting ?in records from Paleozoic rocks. Here, we review data obtained from a large sample collection of Middle to Upper Devonian sections in Belgium. Comparison of ?in trends with paleoenvironmental indicators (facies) and with detrital input proxies (Zr, Th, Ti, Al) allowed to assess the persistence of depositional trends. Furthermore, the ?in signal was deconvolved into its dominant mineralogical contributions with the help of magnetic-property analysis. The main results are pointing to a magnetic signal dominated by fine-grained magnetite, of which paleomagnetic analysis indicated a formation during Carboniferous remagnetization. This prompts a potentially strong influence of post-depositional processes and it complicates the interpretation of ?in records in terms of depositional environments. However, in most of the sections, there is a relatively good relationship between ?in trends and facies evolution and between ?in and geochemical proxies for detrital inputs. This indicates that the newly formed magnetite grains would at least partly remain where they are formed, and this allows a relative preservation of the original signal, despite the strong influence of diagenesis. Two sections show a stronger impact of diagenesis, where for about half of these sections, the primary, depositional information is lost. The Eifelian–Givetian Monts de Baileux section was selected for time-series analysis of the ?in series. The Average Spectral Misfit (ASM) method is applied to explicitly evaluate the null hypothesis of no orbital signal and in this section, there is 99.05% chance that the MS signal is reflecting an orbital imprint.

All data in IMIS is subject to the VLIZ privacy policy Top | Authors