Transmission electron microscopic observation of forsterite (Mg(2)SiO(4)) shocked to peak pressures of 78 to 92 gigapascals revealed that forsterite breaks down to an assemblage of MgO plus MgSiO(3) glass. This strongly supports the interpretation that the high-pressure phase of forsterite under shock compression is due to the assemblage of MgSiO(3) perovskite plus MgO.
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http://dx.doi.org/10.1126/science.214.4517.177 | DOI Listing |
Sci Rep
April 2022
Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, 91125, USA.
Meteorites preserve evidence of processes on their parent bodies, including alteration, metamorphism, and shock events. Here we show that the Kakowa (L6) ordinary chondrite (OC) preserves both shock-melt veins and pockets of detrital grains from a brecciated and altered object, including corundum, albite, silica, fayalite, forsterite, and margarite in a Pb- and Fe-rich matrix. Preservation of the observed mineralogy and texture requires a sequence of at least two impacts: first, a high-velocity collision formed the shock melt veins containing the high-pressure minerals ringwoodite, wadsleyite, majorite, and albitic jadeite; later, a low-velocity impact formed fractures and filled them with the detrital material.
View Article and Find Full Text PDFMaterials (Basel)
February 2022
Faculty of Civil Engineering, Institute of Technology of Building Materials and Components, Brno University of Technology, Veveri 331/95, 602 00 Brno, Czech Republic.
This article aims to investigate the corrosion resistance of novel fly ash-based forsterite-spinel (MgSiO-MgAlO) refractory ceramics to various corrosive media in comparison with reactive alumina-based ceramics. Because fly ash is produced in enormous quantities as a byproduct of coal-burning power stations, it could be utilized as an affordable source of aluminum oxide and silicon oxide. Corrosion resistance to iron, clinker, alumina, and copper was observed by scanning electron microscope with an elemental probe.
View Article and Find Full Text PDFJ Geophys Res Planets
April 2021
Department of Earth and Planetary Sciences U. California Davis CA USA.
The physical processes during planet formation span a large range of pressures and temperatures. Giant impacts, such as the one that formed the Moon, achieve peak pressures of 100s of GPa. The peak shock states generate sufficient entropy such that subsequent decompression to low pressures intersects the liquid-vapor phase boundary.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
October 2020
Ege University, Central Research Testing and Analysis Laboratory Research and Application Center, 35100 Bornova, Izmir, Turkey.
Olivine-ringwoodite and plagioclase-maskelynite transformation mechanisms in the Bursa L6 chondrite were determined by Raman and Attenuated Total Reflectance (ATR)-Fourier Transform Infrared (FTIR) spectroscopic techniques. Forsterite composition was estimated to be 75% by using Raman and IR correlation data. Possible high impact shock pressure for Bursa meteorite was found to be at least 64.
View Article and Find Full Text PDFSci Adv
August 2016
Graduate School of Engineering, Osaka University, Suita 565-0871, Japan.; Photon Pioneers Center, Osaka University, Suita 565-0871, Japan.
Forsterite (Mg2SiO4) is one of the major planetary materials, and its behavior under extreme conditions is important to understand the interior structure of large planets, such as super-Earths, and large-scale planetary impact events. Previous shock compression measurements of forsterite indicate that it may melt below 200 GPa, but these measurements did not go beyond 200 GPa. We report the shock response of forsterite above ~250 GPa, obtained using the laser shock wave technique.
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