Raman spectra of impact zircons in the Jarva-varaka layered massif (the Monchegorsk ore region, the Kola Peninsula)
Journal Title: Вестник МГТУ - Year 2017, Vol 20, Issue 1
Abstract
Zircon crystals from granophyre norites of the Jarva-varaka massif of the Monchegorsk ore region (the Kola Peninsula) have been studied by means of back-scattered electron (BSE) imaging and Raman spectroscopy. The Jarva-varaka massif according to geological and geochemical data has been compared with the Sudbury structure, for which an impact origin is assumed. Zircon study is stipulated by zircon ability to keep signs of shock metamorphism even under granulite-facies conditions, thus it can be used for identification of ancient impact structures. BSE images reveal complicated internal texture – darker central domains (cores) and light rims without texture. Mineral inclusions in zircon are represented by sillimanite and plagioclase which indicates that the studied zircon grains were inherited from the host aluminous gneisses. Zircon crystals show variation of Raman spectra from the core of crystals with typical zircon Raman pattern to complete absence of spectral bands in the marginal parts and rims. Mineral inclusions in zircon rims also have no Raman spectra. Such patterns may be associated with the transformation of crystalline zircon (and mineral inclusions in it) to diaplectic glass under the influence of shock metamorphism, core domains were screened by rims and thus preserved their structure. The received data suggest the participation of the meteorite impact in the formation of the Jarva-varaka massif that requires further investigation.
Authors and Affiliations
T. V. Kaulina, L. I. Nerovich, V. N. Bocharov, L. M. Lyalina, V. L. Il'chenko, E. L. Kunakkuzin, I. A. Kasatkin
Keywords
Related Articles
- EP ID EP216697
- DOI 10.21443/1560-9278-2017-20-1/1-72-82
- Views 158
- Downloads 0
Estimation of aeration time in blind excavations: Methodological approach based on 3D numerical modeling
The paper presents the results on 3D numerical modeling of ventilation in blind excavations of different length under the fixed transverse section due to turbulent diffusion. Aerodynamic characteristics have been calcula...
Effect of extraction technology on antioxidant activity of black chokeberry Aronia melanocarpa, cranberries Vaccinium vitis-idaéa, blueberries Vaccinium myrtillus, raspberries Rubus idaeus, cherries Prunus subg. cérasus, black currant Ribes nigrum
Foods rich in antioxidants and antioxidant activity reduce the risk of many diseases. To solve the urgent task of creating an optimal technology for extracting a complex of substances with antioxidant action from fruits...
Evaluation of the functional activity of activated sludge from local waste water treatment plant in the Arctic region
The paper considers characteristics of the activated sludge in the local wastewater treatment plant (LWTP) and its ability to purify fully domestic sewage water in the Far North. Biochemical process of destruction of org...
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...
On rational usage of catches during the trap fishery in the Barents Sea
The aim of the work is the search for resources to increase the fullness and complexity of using commercial catches of the red king crab and snow crab in the Barents Sea. The causes of the by-catches during the new trap...