Open AccessApplication of an Anisotropy‐Based Correction to Relative Paleointensity Estimates of Experimentally Deposited Sediments
Author(s) -
Molinek F. R.,
Bilardello D.
Publication year - 2018
Publication title -
geochemistry, geophysics, geosystems
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.928
H-Index - 136
ISSN - 1525-2027
DOI - 10.1002/2017gc007196
Subject(s) - geology , sedimentary depositional environment , sedimentary rock , anisotropy , remanence , bioturbation , sediment , natural remanent magnetization , geophysics , isotropy , sedimentary basin , deposition (geology) , mineralogy , earth's magnetic field , magnetization , geochemistry , geomorphology , magnetic field , structural basin , physics , quantum mechanics
The magnetization of a sediment is acquired when ferromagnetic detrital particles align with the Earth's magnetic field as they settle through the water column. The relative continuity and ubiquity of the global sedimentary record makes sediments and sedimentary rocks an ideal target for studies of relative paleointensity (RPI) and the evolution of the Earth's magnetic field. However, processes including flocculation, contact with the substrate, bioturbation, and compaction disrupt this alignment, leading to shallowed remanent inclinations and biased intensities. The inclination of the depositional field also exerts an influence on the remanent intensity, thus affecting RPI estimates and leading to complications in interpretations of the global record. We present a series of 12 deposition experiments conducted in varying field strengths and inclinations, from which we determine RPI estimates. We then correct these estimates using a modified anisotropy‐based inclination correction technique. We find experimentally that our correction reduces the inclination dependence of relative paleointensity while preserving the RPI's dependence on the depositional intensity. Our results suggest that the anisotropy‐based correction should improve RPI estimates obtained from natural sediments and sedimentary rocks.