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DOI	10.1038/s41561-019-0381-z
	Regional stratification at the top of Earth's core due to core–mantle boundary heat flux variations
	Mound J.; Davies C.; Rost S.; Aurnou J.
发表日期	2019
ISSN	17520894
英文摘要	Earth’s magnetic field is generated by turbulent motion in its fluid outer core. Although the bulk of the outer core is vigorously convecting and well mixed, some seismic, geomagnetic and geodynamic evidence suggests that a global stably stratified layer exists at the top of Earth’s core. Such a layer would strongly influence thermal, chemical and momentum exchange across the core–mantle boundary and thus have important implications for the dynamics and evolution of the core. Here we argue that the relevant scenario is not global stratification, but rather regional stratification arising solely from the lateral variations in heat flux at the core–mantle boundary. Using our extensive suite of numerical simulations of the dynamics of the fluid core with heterogeneous core–mantle boundary heat flux, we predict that thermal regional inversion layers extend hundreds of kilometres into the core under anomalously hot regions of the lowermost mantle. Although the majority of the outermost core remains actively convecting, sufficiently large and strong regional inversion layers produce a one-dimensional temperature profile that mimics a globally stratified layer below the core–mantle boundary—an apparent thermal stratification despite the average heat flux across the core–mantle boundary being strongly superadiabatic. © 2019, The Author(s), under exclusive licence to Springer Nature Limited.
来源期刊	Nature Geoscience
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/125096
作者单位	School of Earth and Environment, University of Leeds, Leeds, United Kingdom; Department of Earth and Space Sciences, University of California, Los Angeles, CA, United States
推荐引用方式 GB/T 7714	Mound J.,Davies C.,Rost S.,等. Regional stratification at the top of Earth's core due to core–mantle boundary heat flux variations[J],2019.
APA	Mound J.,Davies C.,Rost S.,&Aurnou J..(2019).Regional stratification at the top of Earth's core due to core–mantle boundary heat flux variations.Nature Geoscience.
MLA	Mound J.,et al."Regional stratification at the top of Earth's core due to core–mantle boundary heat flux variations".Nature Geoscience (2019).