4.8 Article

Formation of large low shear velocity provinces through the decomposition of oxidized mantle

期刊

NATURE COMMUNICATIONS
卷 12, 期 1, 页码 -

出版社

NATURE RESEARCH
DOI: 10.1038/s41467-021-22185-1

关键词

-

资金

  1. Strategic Priority Research Program (B) of the Chinese Academy of Sciences [XDB41000000, XDB18000000]
  2. Natural Science Foundation of China [41925017, 41721002]
  3. Fundamental Research Funds for the Central Universities [WK2080000144]
  4. National Science Foundation (NSF) [EAR-1849949, EAR-1855624]
  5. new faculty startup funding of Michigan State University
  6. NSF [EAR-1664332, EAR2031149]
  7. NASA [NNX15AG54G]
  8. NASA [803513, NNX15AG54G] Funding Source: Federal RePORTER

向作者/读者索取更多资源

Recent studies have shown that the presence of Fe3+-rich bridgmanite in the lowermost mantle can explain the formation of LLSVPs and have significant implications for the storage of redox-sensitive elements in the deep Earth.
Large Low Shear Velocity Provinces (LLSVPs) in the lowermost mantle are key to understanding the chemical composition and thermal structure of the deep Earth, but their origins have long been debated. Bridgmanite, the most abundant lower-mantle mineral, can incorporate extensive amounts of iron (Fe) with effects on various geophysical properties. Here our high-pressure experiments and ab initio calculations reveal that a ferric-iron-rich bridgmanite coexists with an Fe-poor bridgmanite in the 90mol% MgSiO3-10mol% Fe2O3 system, rather than forming a homogeneous single phase. The Fe3+-rich bridgmanite has substantially lower velocities and a higher V-P/V-S ratio than MgSiO3 bridgmanite under lowermost-mantle conditions. Our modeling shows that the enrichment of Fe3+-rich bridgmanite in a pyrolitic composition can explain the observed features of the LLSVPs. The presence of Fe3+-rich materials within LLSVPs may have profound effects on the deep reservoirs of redox-sensitive elements and their isotopes. Dense Fe3+-rich bridgmanite can explain the seismic features of Large Low Shear Velocity Provinces, as it can form large-scale thermochemical piles in the deep mantle that remain stable throughout Earth's history.

作者

我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。

评论

主要评分

4.8
评分不足

次要评分

新颖性
-
重要性
-
科学严谨性
-
评价这篇论文

推荐

暂无数据
暂无数据