气候变化领域集成服务门户(CCPortal): Mind the gap: Towards a biogenic magnetite palaeoenvironmental proxy through an extensive finite-element micromagnetic simulation

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DOI	10.1016/j.epsl.2019.116010
	Mind the gap: Towards a biogenic magnetite palaeoenvironmental proxy through an extensive finite-element micromagnetic simulation
	Berndt T.A.; Chang L.; Pei Z.
发表日期	2020
ISSN	0012821X
卷号	532
英文摘要	Magnetotactic bacteria (MTB) preserved in sediments (magnetofossils) are highly sensitive to environmental and climatic forcing and can therefore be used as an easy-to-measure palaeo-environment proxy. It is known that magnetofossils occur with various morphologies – each with its own particular magnetic signature. We present the first systematic extensive micromagnetic study relating magnetosome chain morphology to their hysteresis parameters. We modelled more than 450 different intact magnetosome chains in the finite-element micromagnetic modelling software MERRILL, relating the morphology (magnetosome size, elongation, intra-chain spacing, and chain length) to the magnetic parameters of coercivity, coercivity of remanence, and saturation magnetization, and analyzing domain-states and switching modes. It is shown that magnetic properties are far dominated by the intra-chain spacing. However, analysis of a large set of published TEM images of different MTB strains shows a strong correlation between intra-chain spacing and grain size. This correlation can in principle be used to infer MTB morphology purely from magnetic measurements, providing a framework to use biogenic magnetite as a sensitive palaeo-environment proxy. Additionally, it is found that MTB carefully control intra-chain spacing during magnetosome synthesis to maximize saturation remanence as well as magnetic stability. © 2019 Elsevier B.V.
关键词	hysteresis magnetosome micromagnetic simulation palaeo-environment proxy
英文关键词	Coercive force; Finite element method; Hysteresis; Magnetic logic devices; Magnetite; Morphology; Saturation magnetization; Coercivity of remanence; magnetosome; Magnetotactic Bacteria; Micromagnetic modelling; Micromagnetic simulations; palaeo-environment; proxy; Saturation remanences; Remanence; finite element method; hysteresis; magnetic field; magnetite; magnetosphere; magnetostratigraphy; numerical model; paleoenvironment; paleomagnetism
语种	英语
来源期刊	Earth and Planetary Science Letters
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/202485
作者单位	Laboratory of Orogenic Belts and Crustal Evolution, School of Earth and Space Sciences, Peking University, Beijing, 100871, China
推荐引用方式 GB/T 7714	Berndt T.A.,Chang L.,Pei Z.. Mind the gap: Towards a biogenic magnetite palaeoenvironmental proxy through an extensive finite-element micromagnetic simulation[J],2020,532.
APA	Berndt T.A.,Chang L.,&Pei Z..(2020).Mind the gap: Towards a biogenic magnetite palaeoenvironmental proxy through an extensive finite-element micromagnetic simulation.Earth and Planetary Science Letters,532.
MLA	Berndt T.A.,et al."Mind the gap: Towards a biogenic magnetite palaeoenvironmental proxy through an extensive finite-element micromagnetic simulation".Earth and Planetary Science Letters 532(2020).