气候变化领域集成服务门户(CCPortal): The Continually Stable Subduction, Iron-Spin Transition, and the Formation of LLSVPs From Subducted Oceanic Crust

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DOI	10.1029/2019JB018262
	The Continually Stable Subduction, Iron-Spin Transition, and the Formation of LLSVPs From Subducted Oceanic Crust
	Huang C.; Leng W.; Wu Z.
发表日期	2020
ISSN	21699313
卷号	125 期号:1
英文摘要	Large low shear velocity provinces (LLSVPs) in the lower mantle beneath Africa and the Pacific Ocean have been widely accepted as compositionally distinct zones characterized by their large spatial scale, distinctive geometry (high topography and steep side boundaries), and long-term stability. One possible explanation for the chemical origin of the LLSVPs is that they formed from subducted oceanic crust. However, some previous geodynamic models suggest that it is difficult for a sufficient quantity of recycled crust to accumulate in the deep mantle and form chemical structures matching those of LLSVPs. Here we show that the continually stable subduction can significantly enhance the gathering of recycled oceanic crust above the core-mantle boundary. The resulting chemical structures in our model show high elevations and steep sides similar to those of the seismically observed LLSVPs when the effects of iron-spin transition in ferropericlase are incorporated. These LLSVP-like structures usually emerge 1–1.5 billion years (Gyr) after the model starts and remain recognizable at 3 Gyr. The total volume of these structures first increases to approximately double the current LLSVPs' volume and then gradually decreases over time. With a subduction pattern corresponding to extroversion supercontinent cycles, two antipodal chemical structures form similar to the current LLSVPs and survive longer than 1 Gyr. ©2020. American Geophysical Union. All Rights Reserved.
英文关键词	iron-spin transition; LLSVPs; Recycled crust; subduction
语种	英语
来源期刊	Journal of Geophysical Research: Solid Earth
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/188033
作者单位	Laboratory of Seismology and Physics of Earth's Interior, School of Earth and Space Sciences, University of Science and Technology of China, Hefei, China; Key Laboratory of Orogenic Belts and Crustal Evolution, School of Earth and Space Sciences, Peking University, Beijing, China; CAS Center for Excellence in Comparative Planetology, Hefei, China
推荐引用方式 GB/T 7714	Huang C.,Leng W.,Wu Z.. The Continually Stable Subduction, Iron-Spin Transition, and the Formation of LLSVPs From Subducted Oceanic Crust[J],2020,125(1).
APA	Huang C.,Leng W.,&Wu Z..(2020).The Continually Stable Subduction, Iron-Spin Transition, and the Formation of LLSVPs From Subducted Oceanic Crust.Journal of Geophysical Research: Solid Earth,125(1).
MLA	Huang C.,et al."The Continually Stable Subduction, Iron-Spin Transition, and the Formation of LLSVPs From Subducted Oceanic Crust".Journal of Geophysical Research: Solid Earth 125.1(2020).