气候变化领域集成服务门户(CCPortal): Femtosecond X-Ray Diffraction of Laser-Shocked Forsterite (Mg2SiO4) to 122 GPa

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DOI	10.1029/2020JB020337
	Femtosecond X-Ray Diffraction of Laser-Shocked Forsterite (Mg2SiO4) to 122 GPa
	Kim D.; Tracy S.J.; Smith R.F.; Gleason A.E.; Bolme C.A.; Prakapenka V.B.; Appel K.; Speziale S.; Wicks J.K.; Berryman E.J.; Han S.K.; Schoelmerich M.O.; Lee H.J.; Nagler B.; Cunningham E.F.; Akin M.C.; Asimow P.D.; Eggert J.H.; Duffy T.S.
发表日期	2021
ISSN	21699313
卷号	126 期号:1
英文摘要	The response of forsterite, Mg2SiO4, under dynamic compression is of fundamental importance for understanding its phase transformations and high-pressure behavior. Here, we have carried out an in situ X-ray diffraction study of laser-shocked polycrystalline and single-crystal forsterite (a-, b-, and c-orientations) from 19 to 122 GPa using the Matter in Extreme Conditions end-station of the Linac Coherent Light Source. Under laser-based shock loading, forsterite does not transform to the high-pressure equilibrium assemblage of MgSiO3 bridgmanite and MgO periclase, as has been suggested previously. Instead, we observe forsterite and forsterite III, a metastable polymorph of Mg2SiO4, coexisting in a mixed-phase region from 33 to 75 GPa for both polycrystalline and single-crystal samples. Densities inferred from X-ray diffraction data are consistent with earlier gas-gun shock data. At higher stress, the response is sample-dependent. Polycrystalline samples undergo amorphization above 79 GPa. For [010]- and [001]-oriented crystals, a mixture of crystalline and amorphous material is observed to 108 GPa, whereas the [100]-oriented forsterite adopts an unknown phase at 122 GPa. The first two sharp diffraction peaks of amorphous Mg2SiO4 show a similar trend with compression as those observed for MgSiO3 in both recent static- and laser-driven shock experiments. Upon release to ambient pressure, all samples retain or revert to forsterite with evidence for amorphous material also present in some cases. This study demonstrates the utility of femtosecond free-electron laser X-ray sources for probing the temporal evolution of high-pressure silicate structures through the nanosecond-scale events of shock compression and release. © 2020. American Geophysical Union. All Rights Reserved.
英文关键词	amorphization; forsterite; phase transition; shock compression
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/187427
作者单位	Department of Geosciences, Princeton University, Princeton, NJ, United States; Now at Earth and Planets Laboratory, Carnegie Institution for Science, Washington, DC, United States; Lawrence Livermore National Laboratory, Livermore, CA, United States; Fundamental Physics Directorate, SLAC National Accelerator Laboratory, Menlo Park, CA, United States; Los Alamos National Laboratory, Los Alamos, NM, United States; Center for Advanced Radiation Sources, University of Chicago, Chicago, IL, United States; European XFEL, Schenefeld, Germany; GFZ German Research Centre for Geosciences, Potsdam, Germany; Now at Department of Earth & Planetary Sciences, Johns Hopkins University, Baltimore, MD, United States; Now at CanmetMINING, Natural Resources Canada, Ottawa, ON, Canada; Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA, United States; Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, United States
推荐引用方式 GB/T 7714	Kim D.,Tracy S.J.,Smith R.F.,et al. Femtosecond X-Ray Diffraction of Laser-Shocked Forsterite (Mg2SiO4) to 122 GPa[J],2021,126(1).
APA	Kim D..,Tracy S.J..,Smith R.F..,Gleason A.E..,Bolme C.A..,...&Duffy T.S..(2021).Femtosecond X-Ray Diffraction of Laser-Shocked Forsterite (Mg2SiO4) to 122 GPa.Journal of Geophysical Research: Solid Earth,126(1).
MLA	Kim D.,et al."Femtosecond X-Ray Diffraction of Laser-Shocked Forsterite (Mg2SiO4) to 122 GPa".Journal of Geophysical Research: Solid Earth 126.1(2021).