Shungite rocks of the Onega Paleoproterozoic structure are volcanogenic-sedimentary Precambrian carbon-bearing formations that vary in genesis, mineral composition, structure and carbon (shungite) content. Shungite rocks have industrially useful properties due to which they can be considered as valuable multifunctional mineral raw materials.
This paper presents the results of the study of the micro heterogeneity of the structural state of shungites of different geneses by Raman spectroscopy and electron microdiffraction.
For the highly ordered shungites gathered from veins in Zazhogino and Maksovo sites, the range of values was significantly higher than for isolated shungite inclusions in the rock. On the contrary, for the Maksovo shungite having the form of separate inclusions in the rock, the spread of the values was much narrower, indicating its lower micro heterogeneity. The value of the coherent scattering region for Chebolaksha shungite was the highest, indicating a maximal structural order. The spread of values for different microareas of the sample is small, which is due to the lower micro heterogeneity of the shungite, and can be associated with the dominance of metamorphism factors over migration processes. Shungite within one site was found to have a structural micro heterogeneity, which varies among occurrences and is associated with their genesis.