High-pressure minerals | American Mineralogist
2019年12月1日 · Pressure-induced structural transformations in rock-forming minerals define the basic divisions of Earth's mantle in the upper mantle, transition zone, and lower mantle. Moreover, the solubility of minor chemical components in these minerals and the occurrence of accessory phases are influential in mixing and segregating chemical elements in ...
Melting at the base of a terrestrial magma ocean controlled by …
2024年7月16日 · The melting behaviour of Earth’s primitive mantle was strongly sensitive to changes in oxygen fugacity, according to high-pressure experiments on pyrolite under different redox conditions.
Structure, Materials and Processes in the Earth’s Core and Mantle
Bridgmanite is believed to be the rheologically strongest phase at high pressure and high temperature among all dominant minerals in the shallower mantle, giving rise to a high viscosity of the lower mantle relative to the upper mantle and the transition low-viscosity zone.
A deeper dive into Earth’s mantle | Science - AAAS
2024年8月8日 · As the mantle slowly moves toward the surface at a rate of 1 cm/year under the Mid-Atlantic Ridge, a geological process called adiabatic decompression melting occurs. This process melts mantle rocks without heat under high pressure and produces buoyant melts.
Mapping Global Lithospheric Mantle Pressure‐Temperature …
2024年4月6日 · Here, we trained machine-learning (ML) algorithms on 985 published high-temperature and high-pressure experiments for use as thermometers and barometers to overcome the limitations of classic methods. We compared our ML models to classic thermobarometers to assess the accuracies of predicted pressures and temperatures.
Early episodes of high-pressure core formation preserved in plume mantle
2018年1月25日 · In this study, we test the hypothesis that Xe and W anomalies in plume mantle were generated by the same process—core formation at high pressures—by quantifying how I partitions between liquid...
The pyrite-type high-pressure form of FeOOH - Nature
2017年7月3日 · Here we report the stability of FeOOH phases at the pressure and temperature conditions of the deep lower mantle, based on first-principles calculations and in situ X-ray diffraction...
Ultrahigh-pressure mantle metasomatism in continental collision …
2023年3月9日 · We report the first identification of metasomatic sources formed at >200 km in continental collision zones that led to the Triassic post-collisional Shidao mafic magmas in the Sulu ultrahigh-pressure terrane, eastern China.
High-Pressure Minerals from the Earth’s Mantle and in Shocked ...
High-pressure silicates and oxides have been found in nature as mineral inclusions in diamonds derived from the Earth’s mantle and as minerals in shocked meteorites and impacted terrestrial rocks. These natural high-pressure minerals are discussed in this chapter.
Deep Mantle Properties | Science - AAAS
2010年1月8日 · High-temperature, high-pressure measurements combined with observation and calculations are providing a better picture of Earth's lower mantle. The lower mantle extends from 660 to 2890 km below the surface of the Earth.