Characterization of Kemer L4 meteorite using Raman spectroscopy, X-ray diffraction, magnetization measurements and...

The bulk interior of Kemer L4 ordinary chondrite was characterized for the first time by means of optical microscopy, scanning electron microscopy with energy dispersive spectroscopy, Raman spectroscopy, X-ray diffraction, magnetization measurements and Mössbauer spectroscopy with a high velocity resolution. The main and minor iron-bearing phases were found as well as ferrihydrite as a result of weathering. The Fe²⁺ partitioning among the M1 and M2 sites in olivine, orthopyroxene and clinopyroxene was determined from the X-ray diffraction. The ratios of Fe²⁺ occupancies for these crystals were estimated from both X-ray diffraction and Mössbauer spectroscopy data and appeared to be in a good agreement. The distribution coefficients K_D and the temperatures of equilibrium cation distribution T_eq were also evaluated for olivine and orthopyroxene from two independent techniques and were in a good consistence: K_D = 1.77, T_eq = 441 K (X-ray diffraction) and K_D = 1.77, T_eq = 439 K (Mössbauer spectroscopy) for olivine and K_D = 0.10, T_eq = 806 K (X-ray diffraction) and K_D = 0.09, T_eq = 787 K (Mössbauer spectroscopy) for orthopyroxene. The fusion crust of Kemer L4 was studied using X-ray diffraction, magnetization measurements and Mössbauer spectroscopy. Magnesioferrite and probably maghemite were found in the fusion crust in addition to other phases observed in the bulk interior.