Shocked Indian meteorites provide clues to Earth’s inaccessible lower mantle

The team of researchers from IIT Kharagpur along with its collaborators have completed a set of complex analyses of the shocked Indian Kamargaon meteorite, sucked by Earth’s Gravity.

In a recent study, a team of researchers from Indian Institute of Technology Kharagpur analysed a shocked meteorite called Kamargaon, fell on November 13, 2015, near the town of Kamargaon, located 27 km away from the Golaghat district of Assam, India. The scientists classified it as a chrondite, a variety of stony meteorite.

In this study, the detailed investigations were carried out by Prof. Sujoy Ghosh and his student, Kishan Tiwari from the Department of Geology and Geophysics of IIT Kharagpur along with the collaborators, Prof. Massaki Miyahara from Hirosima University, Japan and Prof. Dwijesh Ray from Physical Research Laboratory, Ahmedabad. The research findings were published in Geophysical Research Letters of Advancing Earth and Space Science on June 8, 2021 (https://doi.org/10.1029/2021GL093592).

One of the authors this paper, Prof Sujoy Ghosh explained, “This particular kind of meteorite is found in the asteroid belt — formed by accumulation of solid particles during the formation of planets — located between the orbits of Jupiter and Mars. These materials are at times pulled out from the belt due to collision and gravitational forces. These meteorites have survived high-pressure and high-temperature events during their formation and fall on Earth due to the planet’s gravitational pull”.

The Kamargaon meteorite is constituted by several rock-forming minerals, where Olivine is the most abundant. Olivine is considered as an important mineral, found in Earth’s lower mantle. It breaks down into bridgemanite and magnesiowustite in the Earth’s lower mantle which is one of the most important reactions that largely controls the physical and chemical properties of the Earth’s interior.

 This is for the time that researchers have found compositions in a meteorite, when olivine is melted at high temperature and pressures, confirming that the chemical found in the mantle is also present in the asteroid belt.

 “Further, the results suggested that the incongruent melting of olivine may possibly operate as one of the alternative mechanisms of dissociation reaction driving the phase transformation of olivine in the natural systems’, said Kishan Tewari, research scholar of IIT Kharagpur.

Media Contact: Prof Sujoy Ghosh, Assistant Professor

Email: sujoy.ghosh@gg.iitkgp.ac.in, Ph. No.:  +91-3222-283364

Contact: Paramita Dey, Junior Assistant

Email: media@iitkgp.ac.in, Ph. No.: +91-3222-282004