High Shock Pressure Metamorphism Induced Transformations of Olivine and Feldspar in Natun Balijan L4 Chondrite: Evidence from Micro-Raman, Infrared Spectroscopy, X-ray Diffraction and Electron Microprobe Analysis

Abstract

For the first time, the presence of olivine-ringwoodite and plagioclase-maskelynite transformations is reported in Natun Balijan L4 chondrite determined by micro-Raman and infrared spectroscopic techniques with mineral phases characterised by electron microprobe analysis. Micro-Raman spectra reveal trace of ringwoodite, which is independently confirmed with the powder X-ray diffraction analysis. Full width at half maximum data of Raman spectrum reveals structural disordered olivine and pyroxene. The nature of infrared peaks at 639 and 724 cm–1 depicts the presence of maskelynite. Observed maskelynite Raman band at 509 and 581 cm–1 are used to estimate the shock stage of Natun Balijan L4 chondrite as at least S5. The impact metamorphism with a shock pressure of at least 40 GPa is estimated.

Characterization of primary silicate minerals in Earth‐like bodies via Raman spectroscopy

“…By comparing the Raman spectra of these minerals with known reference features, it becomes possible to ascertain whether the minerals have experienced external impacts. [19][20][21][22] Ideally, the intensity of Raman peaks could be used to quantify mineral components. However, utilizing peak intensity for this purpose presents challenges due to factors like laser intensity, mineral crystal phase, and detector response efficiency.…”

“…Intriguingly, Raman peaks undergo shifts when minerals are subjected to impacts. By comparing the Raman spectra of these minerals with known reference features, it becomes possible to ascertain whether the minerals have experienced external impacts 19–22 . Ideally, the intensity of Raman peaks could be used to quantify mineral components.…”