Ilchenko K. The impurity defects and genetic features of Ukrainian Shield microdiamonds (by spectroscopic data)

The thesis deals with a comparative infrared spectroscopic and photoluminescence study of nitrogenous and other defects in microdiamonds from terrigenous rocks of the Ukrainian Shield (USh), Arkhangelsk and Yakutian kimberlites (Russia) and lamproites of Australian Argyle pipe. The data on the main nitrogen and other defects composition and concentration in microdiamonds studied and those from some contrasting world deposits (South Africa, Brasilia, Canada, Kazakhstan and other) were analyzed. Formation conditions of some Ukrainian microdiamonds from all geologic blocks of the USh were found to be close to microdiamonds from different Russian and South-African kimberlites. Some samples from northern and central parts of the USh were probably formed in the asthenosphere or lower mantle. The main spectral features of others (south-west and central parts of the USh) are similar to microdiamonds from minette of Canadian dyke Akluil?k and from Kazakhstan, Norwegian and other metamorphic rocks. The spectroscopic data obtained evidence of different ages and significantly different growth conditions and further thermal history of Ukrainian microdiamonds from every specific placer. Crystallization medium of a part of the samples studied was enriched by volatile components. It is concluded that almost in each geologic block of the USh there might be several genetically different maternal diamond sources.