气候变化领域集成服务门户(CCPortal): Single-Crystal Elasticity of MgSiO3 Bridgmanite to Mid-Lower Mantle Pressure

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DOI	10.1029/2020JB020967
	Single-Crystal Elasticity of MgSiO3 Bridgmanite to Mid-Lower Mantle Pressure
	Criniti G.; Kurnosov A.; Boffa Ballaran T.; Frost D.J.
发表日期	2021
ISSN	21699313
卷号	126 期号:5
英文摘要	The combination of seismic observations and mineral physics data represents a unique tool to understand the structure and evolution of the deep Earth's interior. However, to date, elasticity data on both compressional (vP) and shear (vS) wave velocities of MgSiO3 bridgmanite are limited to shallow mantle conditions, hampering the resolution of mineral physics models. Here, we report the first single-crystal measurements of vP and vS of MgSiO3 bridgmanite up to ∼79 GPa using high-pressure Brillouin scattering and single-crystal X-ray diffraction in a diamond anvil cell. At shallow lower mantle pressures, the elastic anisotropy of MgSiO3 bridgmanite was found to be similar, albeit smaller than that of Fe,Al-bearing bridgmanite of Kurnosov et al. (2017) but differed significantly from that proposed in the recent study of Fu et al. (2019). Using the elastic stiffness coefficients of bridgmanite obtained in this study at different pressures, we calculate the pressure dependence of the adiabatic bulk modulus, KS0 = 257.1(6) GPa, K'S0 = 3.71(4), and of the shear modulus, G0 = 175.6(2) GPa, G'0 = 1.86(1). These elastic parameters are included in a self-consistent thermodynamic model to calculate seismic wave velocities along a lower mantle adiabat for a primitive upper mantle bulk composition in the FeO-CaO-MgO-SiO2 system, which is currently the most complex system for which sufficient data exist. This preliminary model provides a good match to the vS and vP of 1D seismic models, implying that the composition of the lower mantle may be closer to pyrolite, rather than being more bridgmanite rich. © 2021. The Authors.
英文关键词	bridgmanite; Brillouin scattering; lower mantle
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/187132
作者单位	Bayerisches Geoinstitut, University of Bayreuth, Bayreuth, Germany
推荐引用方式 GB/T 7714	Criniti G.,Kurnosov A.,Boffa Ballaran T.,et al. Single-Crystal Elasticity of MgSiO3 Bridgmanite to Mid-Lower Mantle Pressure[J],2021,126(5).
APA	Criniti G.,Kurnosov A.,Boffa Ballaran T.,&Frost D.J..(2021).Single-Crystal Elasticity of MgSiO3 Bridgmanite to Mid-Lower Mantle Pressure.Journal of Geophysical Research: Solid Earth,126(5).
MLA	Criniti G.,et al."Single-Crystal Elasticity of MgSiO3 Bridgmanite to Mid-Lower Mantle Pressure".Journal of Geophysical Research: Solid Earth 126.5(2021).