The inclusion of grothite in the zircon from granitoids of the crystalline basement of the Southern Yamal Peninsula
Journal Title: Вестник МГТУ - Year 2019, Vol 22, Issue 1
Abstract
Grothite – rare F-Al-rich type of titanite – has been found in accessory zircon from the granitoids of the pre-Jurassic basement of the Verkhnerechensky oil-gas area (in the southern part of the Yamal Peninsula) as a result of the study. Titanite forms rare inclusions (so-called minerals-prisoners) in the central parts of zircon crystals; in our sample of 35 individuals only two grains of titanite have been discovered. The measurement of the chemical composition of the mineral has been carried out on an electron-probe microanalyzer CAMECA SX 100, equipped with five wave spectrometers (IGG UrB RAS, Ekaterinburg). According to the microprobe analysis, the mineral has an unusual chemical composition, it shows the presence of significant concentrations of alumina (Al2O3 to 8.5 wt.%), rare earths elements (REE to 4.3 wt.%), and fluorine (F to 2 wt.%). This grothite is dramatically different in chemical composition from the accessory titanite of the matrix granitoid (monzoleicogranite), which is characterized by values close to the reference sphene. Overall, grothite is an intermediate connection between the two extreme members CaTiSiO4O (titanite) – CaAlSiO4F (synthesized Al-F-titanite), and the Verkhnerechensky mineral content of a hypothetical Al-F-titanite achieves a high level of 24–26 %. Unfortunately, grothite is crystallized in a wide range of temperatures and pressures which does not allow its use in thermodynamic reconstructions. The existence of grothite (or Al-F-titanite) is apparently determined not so much on the PT-conditions of rocks' formation, but most likely on the chemistry of the environment. So it is obvious that the Verkhnerechensky titanite was formed in the melt with an increased concentration of fluorine. It is the first record of grothite in the form of inclusions in accessory zircon.
Authors and Affiliations
Yu. V. Erokhin, K. S. Ivanov, V. V. Khiller
Keywords
Related Articles
- EP ID EP514157
- DOI 10.21443/1560-9278-2019-22-1-5-11
- Views 107
- Downloads 0
Metal content in bottom sediments of the central part of the Pechora Sea in the current period
Based on the data from the marine researches of Knipovich Polar Research Institute of Marine Fisheries and Oceanography (PINRO) carried out in the period of 2010–2015, the content of some metals in bottom sediments of th...
Factor analysis of ways to activate using the urban passenger motor transport
The deterioration in the quality of transport services to the population with simultaneous increasing the number of motor vehicles leads to aggravation of the accumulated problems in the sphere of passenger transport. Th...
The use of plant enriching additives in the production of pasta: Literature review
The quality of food and the overall balance of the human diet are crucial for the health and quality of life. Food industry enterprises produce functional and enriched food products, but their quantity is not enough toda...
Exterior indicators and physiological signs' indices of juveniles Salmo salar L. in the rivers of the Kola Peninsula
The range of background values of main parameters of the exterior and indices of morphophysiological features of autumn juvenile salmon Salmon salar L. in four rivers of the Kola Peninsula not affected by hatchery produc...
Cryoextrusion in technology of fish feed production
The process of grinding the frozen fish raw materials using the useful model of a piston-type extruder with cooled working bodies has been investigated. A new feed product – cryo minced fish feed – has been obtained. The...