English
Related papers

Related papers: Opaque Lowermost Mantle

200 papers

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…

Thermal conductivity of the lowermost mantle governs the heat flow out of the core energizing planetary-scale geological processes. Yet, there are no direct experimental measurements of thermal conductivity at relevant pressure-temperature…

Earth's lower mantle is generally believed to be seismically and chemically homogeneous because most of the key seismic parameters can be explained using a simplified mineralogical model at expected press-temperature conditions. However,…

Materials Science · Physics 2017-04-06 Shenzhen Xu , Jung-Fu Lin , Dane Morgan

The ability of Earths mantle to conduct heat by radiation is determined by optical properties of mantle phases. Optical properties of mantle minerals at high pressure are accessible through diamond anvil cell experiments, but because of the…

Geophysics · Physics 2016-04-12 Sergey S. Lobanov , Nicholas Holtgrewe , Alexander F. Goncharov

The Earth acts as a gigantic heat engine driven by decay of radiogenic isotopes and slow cooling, which gives rise to plate tectonics, volcanoes, and mountain building. Another key product is the geomagnetic field, generated in the liquid…

Geophysics · Physics 2015-06-04 Monica Pozzo , Chris Davies , David Gubbins , Dario Alfè

Seismic mapping of the top of the inner core indicates two distinct areas of high P-wave velocity, the stronger one located beneath Asia, and the other located beneath the Atlantic. This two-fold pattern supports the idea that a…

Geophysics · Physics 2024-08-07 Aditya Varma , Binod Sreenivasan

The Earth's lower mantle hosts a subtle but pervasive quantum phenomenon: the pressure-induced spin crossover of iron in its dominant minerals, bridgmanite and ferropericlase. In this transition, iron ions gradually shift from high-spin to…

A cosmological model, in which the cosmic microwave background (CMB) is a thermal radiation of intergalactic dust instead of a relic radiation of the Big Bang, is revived and revisited. The model suggests that a virtually transparent local…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-30 Vaclav Vavrycuk

For the past few centuries, the temporal variation in the Earth's magnetic field in the Pacific region has been anomalously low. The reason for this is tied to large scale flows in the liquid outer core near the core-mantle boundary, which…

Geophysics · Physics 2022-01-05 Mathieu Dumberry , Colin More

The temperature anomalies in the Earth's mantle associated with thermal convection1 can be inferred from seismic tomography, provided that the elastic properties of mantle minerals are known as a function of temperature at mantle pressures.…

Materials Science · Physics 2017-10-25 A. R. Oganov , J. P. Brodholt , G. D. Price

Periodic variations in the Sun and Moon's gravitational pull cause small changes in Earth's rotational axis direction called nutation. Nutation components in the retrograde quasi-diurnal frequency band measured in the terrestrial reference…

Earth and Planetary Astrophysics · Physics 2025-07-14 J. Rekier , S. A. Triana , A. Barik , D. Abdulah , W. Kang

Earth's interior consists primarily of an insulating rocky mantle and a metallic iron-dominant core. Recent work has shown that mountain-scale structures at the core-mantle boundary may be highly enriched in FeO reported to exhibit high…

The thermoelastic properties of ferropericlase Mg1-xFexO (x = 0.1875) throughout the iron high-to-low spin crossover have been investigated by first principles at Earth's lower mantle conditions. This crossover has important consequences…

Materials Science · Physics 2013-07-15 R. M. Wentzcovitch , J. F. Justo , Z. Wu , C. R. S. da Silva , D. A. Yuen , D. Kohlstedt

The iron spin crossover in ferropericlase introduces anomalies in its thermodynamics and thermoelastic properties. Here we investigate how these anomalies can affect the lower mantle geotherm. The effect is examined in mantle aggregates…

Thermal conductivity ($\kappa$) of mantle minerals is a fundamental property in geodynamic modeling. It controls the style of mantle convection and the time scale of the mantle and core cooling. Cubic CaSiO$_3$ perovskite (CaPv) is the…

Materials Science · Physics 2021-11-17 Zhen Zhang , Dong-Bo Zhang , Kotaro Onga , Akira Hasegawa , Kenji Ohta , Kei Hirose , Renata M. Wentzcovitch

Torsional Alfv{\'e}n waves propagating in the Earth's core have been inferred by inversion techniques applied to geomagnetic models. They appear to propagate across the core but vanish at the equator, exchanging angular momentum between…

Geophysics · Physics 2016-07-06 Nathanaël Schaeffer , Dominique Jault

The composition of the lower mantle $-$ comprising 56% of Earth's volume $-$ remains poorly constrained. Among the major elements, Mg/Si ratios ranging from $\sim$0.9$-$1.1, such as in rocky solar-system building blocks (or chondrites), to…

Earth and Planetary Astrophysics · Physics 2018-03-22 Maxim D. Ballmer , Christine Houser , John W. Hernlund , Renata M. Wentzcovitch , Kei Hirose

The Earth's magnetic field is generated by a dynamo in the outer core and is crucial for shielding our planet from harmful radiation. Despite the established importance of the core-mantle boundary heat flux as driver for the dynamo, open…

In Luparello et al. 2023, a new and hitherto unknown CMB foreground was detected. A systematic decrease in Cosmic Microwave Background (CMB) temperatures around nearby large spiral galaxies points to an unknown interaction with CMB photons…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-19 Frode K. Hansen , Ezequiel F. Boero , Heliana E. Luparello , Diego Garcia Lambas
‹ Prev 1 2 3 10 Next ›