气候变化领域集成服务门户(CCPortal): Blocked radiative heat transport in the hot pyrolitic lower mantle

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DOI	10.1016/j.epsl.2020.116176
	Blocked radiative heat transport in the hot pyrolitic lower mantle
	Lobanov S.S.; Holtgrewe N.; Ito G.; Badro J.; Piet H.; Nabiei F.; Lin J.-F.; Bayarjargal L.; Wirth R.; Schreiber A.; Goncharov A.F.
发表日期	2020
ISSN	0012821X
卷号	537
英文摘要	The heat flux across the core-mantle boundary (QCMB) is the key parameter to understand the Earth's thermal history and evolution. Mineralogical constraints of the QCMB require deciphering contributions of the lattice and radiative components to the thermal conductivity at high pressure and temperature in lower mantle phases with depth-dependent composition. Here we determine the radiative conductivity (krad) of a realistic lower mantle (pyrolite) in situ using an ultra-bright light probe and fast time-resolved spectroscopic techniques in laser-heated diamond anvil cells. We find that the mantle opacity increases critically upon heating to ∼3000 K at 40-135 GPa, resulting in an unexpectedly low radiative conductivity decreasing with depth from ∼0.8 W/m/K at 1000 km to ∼0.35 W/m/K at the CMB, the latter being ∼30 times smaller than the estimated lattice thermal conductivity at such conditions. Thus, radiative heat transport is blocked due to an increased optical absorption in the hot lower mantle resulting in a moderate CMB heat flow of ∼8.5 TW, on the lower end of previous QCMB estimates based on the mantle and core dynamics. This moderate rate of core cooling implies an inner core age of about 1 Gy and is compatible with both thermally- and compositionally-driven ancient geodynamo. © 2020 Elsevier B.V.
关键词	core-mantle boundary diamond anvil cell high pressure thermal conductivity time-resolved spectroscopy
英文关键词	Heat flux; Heat transfer; Laser spectroscopy; Light absorption; Core-mantle boundary; Diamond-anvil cell; High pressure; High-pressure and temperatures; Laser-heated diamond anvil cells; Lattice thermal conductivity; Radiative conductivity; Time-resolved spectroscopy; Thermal conductivity; core-mantle boundary; diamond anvil cell; geodynamo; heat transfer; high pressure; inner core; lower mantle; radiative transfer; spectroscopy; thermal conductivity; Calluna vulgaris
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/202755
作者单位	Geophysical Laboratory, Carnegie Institution of Washington, Washington, DC 20015, United States; Department of Geosciences, Stony Brook University, Stony Brook, NY 11794, United States; GFZ German Research Centre for Geosciences, Telegrafenberg, Potsdam, 14473, Germany; Center for Advanced Radiation Sources, University of ChicagoIL 60637, United States; CNRS, Centre de Recherches Pétrographiques et Géochimiques, Vandoeuvre, 54500, France; Institut de physique du globe de Paris, Université de Paris, CNRS, Paris, 75005, France; Earth and Planetary Science Laboratory, Ecole Polytechnique Fédérale de Lausanne, Lausanne, CH-1015, Switzerland; Centre Interdisciplinaire de Microscopie Electronique, Ecole Polytechnique Fédérale de Lausanne, Lausanne, CH-1015, Switzerland; Department of Geological Sciences, Jackson School of Geosciences, The University of Texas at Austin, Austin, TX 78712, United States; Institute of Geosciences, Goethe University Frankfurt am Main, Frankfurt am Main, Germany; Key Laboratory o...
推荐引用方式 GB/T 7714	Lobanov S.S.,Holtgrewe N.,Ito G.,et al. Blocked radiative heat transport in the hot pyrolitic lower mantle[J],2020,537.
APA	Lobanov S.S..,Holtgrewe N..,Ito G..,Badro J..,Piet H..,...&Goncharov A.F..(2020).Blocked radiative heat transport in the hot pyrolitic lower mantle.Earth and Planetary Science Letters,537.
MLA	Lobanov S.S.,et al."Blocked radiative heat transport in the hot pyrolitic lower mantle".Earth and Planetary Science Letters 537(2020).