No abstract

No abstract

No abstract

No abstract

The Pizhemskoye titanium deposit (Middle Timan) has become one of the most attractive deposits for the industrial development in Russia as a result of the successful protection and approval of reserves at the State Reserves Committee (November 2020). 60 years have passed since the first finds of titanium mineralization in the basin of the Pechora Pizhma and Umba rivers by the thematic teams of the Ukhta Geological Exploration Department and the Komi branch of the Academy of Sciences, and now the deposit is considered one of the largest in Russia and the World. Together with the Yarega oil-titanium deposit, they contain up to 80% of the reserves and predicted resources of titanium in Russia. Timan becomes the largest raw material base of titanium in the world, the intensive development of which is possible for several hundred years. The article highlights the geological structure of the Pizhemskoye deposit (revealed a cellular, bowl-like structure of ore bodies); material and complex polymineral composition of ores; the Neoproterozoic age. The author proves the hydrothermal-metamorphogenic genesis of the ores, considers the sources of the mineral matter and solution of the technological scheme for processing refractory ores. The Pizhemskoye deposit is classified as a new pseudorutile-leucoxene-quartz subtype of primary metamorphogenic deposits.

No abstract

A study on the typomorphic characteristics and age of the monazite the two giant titanium deposits of the Timan – Pizhemskoye and Yarega, which revealed differences in morphology in the species composition of the inclusions, the grain size, distribution of chemical types of a mineral associated with conditions of crystallization and different sources of the substance. The isochronous Th-Pb monazite age was calculated using the «CHIME» method. For Yarega monazite built three isochrone with age 1301, 1105 and 778 Ma; for Pizhemsky monazite-kularite one isochrone with age 782 Ma. Source of hith-Th monazite Yarega oil-titanium deposit could be ancient granite batholith and the origin Yarega less-Th monazite and Nd-Ce-monazite-kularite Pizhemskoye deposit with an age of ~ 780 Ma could be related to the hydrothermal conversion of the weathering crusts on lamprophyres close in age with lamprophyre (spessartite and kersantite) of Chetlassky Kamen.

The article critically analysesthe hypotheses about the formation, age, and sources of material of large Timan titanium deposits, which were previously considered ancient buried placers formed along the weathering crusts of the Riphean shales. We discuss an alternative hydrothermal-metamorphic hypothesis about the formation of these deposits and the source of ore material. It is established that the incoming zircon of different ages (570-3200 Ma), as well as two other geochronometers, rutile and monazite, underwent a thermal effect common for all varieties as a result of a hydrothermal process about 600 Ma ago. According to modern concepts, the closing temperature of the U-Pb system in rutile exceeds 500 °С, which suggests high-temperature conditions for the hydrothermal processing of rutile during the formation of the considered deposits in the Riphean.