Parageneses of Garnet Inclusions in Diamonds From Yakutia Kimberlites Based on Raman and IR Spectroscopy Data

Resumo

Diamonds with garnet inclusions have been studied from the Udachnaya, Zapolyarnaya, Komsomolskaya-Magnitnaya, Yubileynaya, Komsomolskaya, Aikhal, Mir, and Mayskaya kimberlite pipes of the Yakutia diamondiferous province. A positive correlation has been revealed between the positions of the main peaks in the Raman spectra of garnets and their chemical composition. A method for determining the paragenetic association of garnet inclusions by the Raman spectroscopy data is described. Diamonds with garnet inclusions of eclogite paragenesis are characterized by a high total nitrogen content and medium degree of aggregation, whereas diamonds with garnet inclusions with dunite–harzburgite and lherzolite parageneses are distinguished by a low nitrogen concentration and a wide variation in the degree of nitrogen aggregation. Dependences have also been revealed between the thermal–temporal parameters of diamond formation (according to IR spectroscopy of diamonds) and type of rocks (according to Raman spectroscopy of garnet inclusions).