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Perovskite retrieved from the lower mantle
Science, 2021The calcium silicate compound was characterized and named as “davemaoite”
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The viscosity of the lower mantle
Journal of Geophysical Research, 1966The viscosity of the mantle is important to theories of convection and continental drift and also to the understanding of the earth's external gravity field. Until recently, however, the processes causing creep in solids under the low stresses present within the earth were obscure, and there were no estimates of the viscosity of the lower mantle.
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Physics of the Earth and Planetary Interiors, 1981
Abstract The rheology of the lower mantle of the Earth is examined from the viewpoint of solid state physics. Recent developments in high-pressure research suggest that the lower mantle contains a considerable amount of (Mg, Fe)O with Fe/Mg + Fe = 0.2–0.3.
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Abstract The rheology of the lower mantle of the Earth is examined from the viewpoint of solid state physics. Recent developments in high-pressure research suggest that the lower mantle contains a considerable amount of (Mg, Fe)O with Fe/Mg + Fe = 0.2–0.3.
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Is the lower mantle homogeneous?
Journal of Geodynamics, 1984Abstract Comparison of some array dt/dΔ studies with the global travel times of Dziewonski and Anderson (1983) leads to the conclusion that a discontinuity in the P travel times between 80° and 85° is consistent with both sets of data. This discontinuity in dt/dΔ corresponds to an increase in velocity of about 0.1 km/sec between depths of 2400 and ...
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Structure and Dynamics of Earth's Lower Mantle
Science, 2008Processes within the lowest several hundred kilometers of Earth's rocky mantle play a critical role in the evolution of the planet. Understanding Earth's lower mantle requires putting recent seismic and mineral physics discoveries into a self-consistent, geodynamically feasible context.
Edward J, Garnero, Allen K, McNamara
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Spin Transition in Magnesiowüstite in Earth’s Lower Mantle
Physical Review Letters, 2006Iron in the major lower mantle (LM) minerals undergoes a high spin (HS) to low spin (LS) transition at relevant pressures (23-135 GPa). Previous failures of standard first principles approaches to describe this phenomenon have hindered its investigation and the clarification of important consequences. Using a rotationally invariant formulation of LDA +
Tsuchiya, T. +3 more
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Iron Partitioning in Earth's Mantle: Toward a Deep Lower Mantle Discontinuity
Science, 2003We measured the spin state of iron in ferropericlase (Mg 0.83 Fe 0.17 )O at high pressure and found a high-spin to low-spin transition occurring in the 60- to 70-gigapascal pressure range, corresponding to depths of 2000 kilometers in Earth's lower mantle.
Badro, J. +6 more
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A Lower Mantle Source for Central European Volcanism
Science, 1999Cenozoic rifting and volcanism in Europe have been associated with either passive or active mantle upwellings. Tomographic images show a low velocity structure between 660- and 2000-kilometer depth, which we propose to represent a lower mantle upwelling under central Europe that may feed smaller upper-mantle plumes.
Goes, S., Spakman, W., Bijwaard, H.
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2017
Diamond contains mineral inclusions of all three lower-mantle associations, juvenile ultramafic, mafic and carbonatitic; it is also an accessory mineral in all these associations. While the first two associations coexist with diamond, the carbonatitic association is a parental medium for the lower-mantle diamond.
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Diamond contains mineral inclusions of all three lower-mantle associations, juvenile ultramafic, mafic and carbonatitic; it is also an accessory mineral in all these associations. While the first two associations coexist with diamond, the carbonatitic association is a parental medium for the lower-mantle diamond.
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The physical and chemical composition of the lower mantle
Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 2005This article reviews some of the recent advances made within the field of mineral physics. In order to link the observed seismic and density structures of the lower mantle with a particular mineral composition, knowledge of the thermodynamic properties of the candidate materials is required.
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