Thermal processing and crystallization of amorphous Mg-Ca silicates

DOI: 10.1111/maps.12162

Authors: Sarah Day (University of Keele) , Stephen Thompson (Diamond Light Source) , Aneurin Evans (Keele University) , Julia Parker (Diamond Light Source) , Leigh Connor (Diamond Light Source) , Chiu Tang (Diamond Light Source)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Meteoritics & Planetary Science , VOL 48 (8) , PAGES 1459-–1471

State: Published (Approved)
Published: July 2013
Diamond Proposal Number(s): 6515 , 7124

Abstract: The structural evolution of sol–gel-produced amorphous Mg(x)Ca(1–x)SiO3 silicates is investigated. Mid-IR Fourier transform infrared spectroscopy and synchrotron X-ray diffraction are used to confirm the amorphous nature of the as-prepared silicates, while subsequent in situ synchrotron X-ray powder diffraction measurements are used to study the evolution of crystalline mineral phases as a function of annealing temperature. Multiple silicate phases, including diopside, enstatite, forsterite, and SiO2, are identified, while Rietveld (i.e., structure) refinement of the diffraction data is used to quantify phase change relationships. Investigated as possible analogs for the refractory dust grain materials likely to have been present in the early solar nebula, the likely relevance of these investigations to the observed silicate compositions of chondritic meteorites and cometary bodies and the processing of their precursor materials is discussed.

Journal Keywords: Mg-Ca silicates; meteorites

Subject Areas: Environment, Chemistry


Instruments: I11-High Resolution Powder Diffraction , I12-JEEP: Joint Engineering, Environmental and Processing