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DOI	10.1016/j.epsl.2020.116345
	The seismically fastest chemical heterogeneity in the Earth's deep upper mantle—implications from the single-crystal thermoelastic properties of jadeite
	Hao M.; Zhang J.S.; Pierotti C.E.; Zhou W.-Y.; Zhang D.; Dera P.
发表日期	2020
ISSN	0012821X
卷号	543
英文摘要	Jadeite is a major mineral phase (up to 50 vol%) in the subducted sediments/crust with continental origin, which are one of the major heterogeneities and important enriched geochemical reservoirs (such as EM-1 and EM-2) for incompatible elements in the Earth's interior. Identifying and locating the enriched geochemical heterogeneities requires knowledge of the elastic properties of relevant mineral phases at high pressure-temperature conditions. Unfortunately, the single-crystal elastic properties of jadeite have never been measured at high-pressure conditions, partially due to its low crystal symmetry. In this study, we have experimentally determined the single-crystal elastic moduli of jadeite at high pressures for the first time up to 18 GPa at the ambient temperature condition using Brillouin spectroscopy. Fitting the third-order finite strain equation of state to the velocity-pressure data yields KS0 ′=3.9(1), G0 ′=1.09(4) with ρ0=3.302(5) g/cm3, KS0=138(3) GPa, and G0=84(2) GPa. In addition, we have also conducted synchrotron single-crystal X-ray diffraction experiments up to 25 GPa and 700 K. The fitting of a Holland-Powell type thermal-pressure Birch-Murnaghan equation of state yields KT0 ′=3.8(2) and α0=3.4(5) ×10−5 K−1. Based on the obtained thermoelastic parameters of jadeite, the density and seismic velocities of continent-derived sediments/crust are modeled at the depth range from 200 to 500 km. The seismic velocities of the subducted continental sediments/crust become extremely fast at depths greater than ∼300 km, up to 11.8% and 14.7% faster than the Vp and Vs of the ambient mantle, and 5.6% and 7.3% faster than the Vp and Vs of the subducted oceanic crust. The existence of even a small amount of the subducted continental sediments/crust can result in strong seismic anomalies in the Earth's interior. © 2020 Elsevier B.V.
关键词	continent-derived sediments/crust enriched geochemical reservoirs jadeite seismic velocity single-crystal elasticity
英文关键词	Elasticity; Equations of state of solids; Geochemistry; Sediments; Seismic waves; Seismology; Silicate minerals; Single crystals; Thermoelasticity; Birch-Murnaghan equation of state; Chemical heterogeneities; Finite strain equations; Geochemical heterogeneity; High-pressure condition; Single crystal x-ray diffraction; Temperature conditions; Thermoelastic properties; Crystal symmetry; heterogeneity; high pressure; jadeite; seismic velocity; subduction; temperate environment; thermoelasticity; upper mantle
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/202631
作者单位	Department of Earth and Planetary Sciences, University of New Mexico, Albuquerque, NM 87131, United States; Institute of Meteoritics, University of New Mexico, Albuquerque, NM 87131, United States; Albuquerque High School, Albuquerque, NM 87102, United States; Hawaii Institute of Geophysics and Planetology, University of Hawaii at ManoaHI 96822, United States; GeoSoiEnviroCARS, University of Chicago, Argonne National Laboratory, Argonne, IL 60439, United States
推荐引用方式 GB/T 7714	Hao M.,Zhang J.S.,Pierotti C.E.,等. The seismically fastest chemical heterogeneity in the Earth's deep upper mantle—implications from the single-crystal thermoelastic properties of jadeite[J],2020,543.
APA	Hao M.,Zhang J.S.,Pierotti C.E.,Zhou W.-Y.,Zhang D.,&Dera P..(2020).The seismically fastest chemical heterogeneity in the Earth's deep upper mantle—implications from the single-crystal thermoelastic properties of jadeite.Earth and Planetary Science Letters,543.
MLA	Hao M.,et al."The seismically fastest chemical heterogeneity in the Earth's deep upper mantle—implications from the single-crystal thermoelastic properties of jadeite".Earth and Planetary Science Letters 543(2020).