1974 -1979 Student, Department of Geology, St. Petersburg University in Russia 1979 -1997 Scientist, All Russia Geological Institute 1990 - Candidate of scientic (Ph.D) degree. Dr. pH. thesis is (1989) "Physico - chemical model of diamond formation in the upper mantie" (scientific leader prof. Perchuk L.L.) 1992 - 1995 Scientist, Institute Experimental Petrology, Chernogolovka, Russia. 1997 - 2008 Scientist, Depart. of Geology, St. Petersburg University in Russia 2003 - Doctor of science degree. Dr. "Physico - chemical aspects of diamond - bearing eclogite parageneses formation" . Nowdats - my company LLC ADAMANT is the official paticipant of Skolkovo. I also collaborate with the company ALROSA doing the criteria for the estimation of kimberlite diamond potential ability Address: Saint Petersburg, St.-Petersburg, Russia
P-T- Oxygen fugacity (fO2) conditions and fluid compositions were estimated for the formation con... more P-T- Oxygen fugacity (fO2) conditions and fluid compositions were estimated for the formation conditions of pyrope garnet inclusions in diamonds and xenocrysts from diamond-bearing and diamond-free kimberlites using their total chemical analyses and single oxythermobarometry. Our data indicate that optimal conditions for diamond growth and preservation occur in the presumed water-rich mantle fluids containing the lowest abundance of free atomic carbon. The majority of the calculated C-H-O fluid compositions for diamond formation in peridotite xenoliths from high diamond grade kimberlites correspond to a high hydrogen and low carbon and oxygen atomic fluid percents, while those from the majority of peridotite xenoliths in the low grade diamond kimberlites corresponds to the low hydrogen, high carbon and oxygen atomic percent fluids. This new approach defines the conditions of diamond formation for kimberlitic deposits. It better characterizes diamond grades in kimberlites in comparis...
Mafic boudins found at Viared in the central Eastern Segment display mineralogical and textural f... more Mafic boudins found at Viared in the central Eastern Segment display mineralogical and textural features which show that these rocks have been eclogites. This discovery together with occurrences of relict eclogites along the Mylonite Zone suggests that the whole of the Eastern Segment was subjected to eclogite facies. The mafic boudins found are hornblende-plagioclase amphibolite, but the interiors show evidence
Nanosized diamond particles in the interstellar space and in the Earth rocks related with water p... more Nanosized diamond particles in the interstellar space and in the Earth rocks related with water presence. In the paper proposed the model of the nanosized diamond particle formation from oxidized water-carbon dioxide gaseous mixtures.
DESCRIPTION Garnet–clinopyroxene barometer is proposed for mantle eclogites on the basis of CaTs ... more DESCRIPTION Garnet–clinopyroxene barometer is proposed for mantle eclogites on the basis of CaTs solubility in clinopyroxene coexisting with garnet. Such barometers permit estimation of P–T conditions for eclogite garnet–clinopyroxene assemblages for the ranges 1150≤ T≤1700 °C and 3 ≤ P≤10 GPa. The barometer were used to determine formation conditions of eclogitic inclusions in diamonds, diamondbearing and diamond-free eclogites from kimberlite pipes.
DESCRIPTION The composition of the C–O–H fluid is estimated on the basis of the composition of il... more DESCRIPTION The composition of the C–O–H fluid is estimated on the basis of the composition of ilmenite xenocrysts. The P–T parameters and oxygen fugacity were assessed for peridotitic ilmenites from the diamond and diamond�free kimberlites of Africa and Yakutia. The composition of the equilibrium C–O–H fluid for these conditions was calculated. The diamond and diamond�free pipes of Angola and Yakutia are characterized by the H2O-rich and CO2-rich fluids, respectively. The results indicate that estimation of the composition of the C–O–H fluid in equilibrium with picroilmenite fits the necessary petrological criteria and may be applied for assessment of the diamond potential of mantle objects.
Most of Earth's diamonds are connected with deep-seated mantle rocks; however, in recent year... more Most of Earth's diamonds are connected with deep-seated mantle rocks; however, in recent years, μm-sized diamonds have been found in shallower metamorphic rocks, and the process of shallow-seated diamond formation has become a hotly debated topic. Nanodiamonds occur mainly in chondrite meteorites associated with organic matter and water. They can be synthesized in the stability field of graphite from organic compounds under hydrothermal conditions. Similar physicochemical conditions occur in serpentinite-hosted hydrothermal systems. Herein, we report the first finding of nanodiamonds, primarily of 6 and 10 nm, in Hyblean asphaltene-bearing serpentinite xenoliths (Sicily, Italy). The discovery was made by electron microscopy observations coupled with Raman spectroscopy analyses. The finding reveals new aspects of carbon speciation and diamond formation in shallow crustal settings. Nanodiamonds can grow during the hydrothermal alteration of ultramafic rocks, as well as during the ...
P-T- Oxygen fugacity (fO2) conditions and fluid compositions were estimated for the formation con... more P-T- Oxygen fugacity (fO2) conditions and fluid compositions were estimated for the formation conditions of pyrope garnet inclusions in diamonds and xenocrysts from diamond-bearing and diamond-free kimberlites using their total chemical analyses and single oxythermobarometry. Our data indicate that optimal conditions for diamond growth and preservation occur in the presumed water-rich mantle fluids containing the lowest abundance of free atomic carbon. The majority of the calculated C-H-O fluid compositions for diamond formation in peridotite xenoliths from high diamond grade kimberlites correspond to a high hydrogen and low carbon and oxygen atomic fluid percents, while those from the majority of peridotite xenoliths in the low grade diamond kimberlites corresponds to the low hydrogen, high carbon and oxygen atomic percent fluids. This new approach defines the conditions of diamond formation for kimberlitic deposits. It better characterizes diamond grades in kimberlites in comparis...
Mafic boudins found at Viared in the central Eastern Segment display mineralogical and textural f... more Mafic boudins found at Viared in the central Eastern Segment display mineralogical and textural features which show that these rocks have been eclogites. This discovery together with occurrences of relict eclogites along the Mylonite Zone suggests that the whole of the Eastern Segment was subjected to eclogite facies. The mafic boudins found are hornblende-plagioclase amphibolite, but the interiors show evidence
Nanosized diamond particles in the interstellar space and in the Earth rocks related with water p... more Nanosized diamond particles in the interstellar space and in the Earth rocks related with water presence. In the paper proposed the model of the nanosized diamond particle formation from oxidized water-carbon dioxide gaseous mixtures.
DESCRIPTION Garnet–clinopyroxene barometer is proposed for mantle eclogites on the basis of CaTs ... more DESCRIPTION Garnet–clinopyroxene barometer is proposed for mantle eclogites on the basis of CaTs solubility in clinopyroxene coexisting with garnet. Such barometers permit estimation of P–T conditions for eclogite garnet–clinopyroxene assemblages for the ranges 1150≤ T≤1700 °C and 3 ≤ P≤10 GPa. The barometer were used to determine formation conditions of eclogitic inclusions in diamonds, diamondbearing and diamond-free eclogites from kimberlite pipes.
DESCRIPTION The composition of the C–O–H fluid is estimated on the basis of the composition of il... more DESCRIPTION The composition of the C–O–H fluid is estimated on the basis of the composition of ilmenite xenocrysts. The P–T parameters and oxygen fugacity were assessed for peridotitic ilmenites from the diamond and diamond�free kimberlites of Africa and Yakutia. The composition of the equilibrium C–O–H fluid for these conditions was calculated. The diamond and diamond�free pipes of Angola and Yakutia are characterized by the H2O-rich and CO2-rich fluids, respectively. The results indicate that estimation of the composition of the C–O–H fluid in equilibrium with picroilmenite fits the necessary petrological criteria and may be applied for assessment of the diamond potential of mantle objects.
Most of Earth's diamonds are connected with deep-seated mantle rocks; however, in recent year... more Most of Earth's diamonds are connected with deep-seated mantle rocks; however, in recent years, μm-sized diamonds have been found in shallower metamorphic rocks, and the process of shallow-seated diamond formation has become a hotly debated topic. Nanodiamonds occur mainly in chondrite meteorites associated with organic matter and water. They can be synthesized in the stability field of graphite from organic compounds under hydrothermal conditions. Similar physicochemical conditions occur in serpentinite-hosted hydrothermal systems. Herein, we report the first finding of nanodiamonds, primarily of 6 and 10 nm, in Hyblean asphaltene-bearing serpentinite xenoliths (Sicily, Italy). The discovery was made by electron microscopy observations coupled with Raman spectroscopy analyses. The finding reveals new aspects of carbon speciation and diamond formation in shallow crustal settings. Nanodiamonds can grow during the hydrothermal alteration of ultramafic rocks, as well as during the ...
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