Variations in the composition and origin of hydrocarbon gases from inclusions in minerals of the Khibiny and Lovozero plutons,Kola Peninsula,Russia |
| |
Authors: | V A Nivin |
| |
Institution: | 1.Geological Institute, Kola Science Center,Russian Academy of Sciences,Apatity, Murmansk oblast,Russia |
| |
Abstract: | Relationships between methane and its homologues mainly contained in fluid microinclusions have been studied in 332 monomineralic
fractions from the Khibiny and Lovozero alkaline plutons. Hydrocarbon gases (HCG) were extracted for subsequent chromatographic
analysis using the bulk method of sample comminution. The molecular weight distribution (MWD) of gaseous alkanes in the same
and associated minerals is different depending on geological setting of the samples. The molecular mass of HCG increases (i)
with decrease in temperature and capture of fluid inclusions in the course of transformation of primary magmatic minerals
and the formation of late minerals as products of intensified postmagmatic processes; (ii) in the direction from khibinite
at the margin and foyaite in the core of the Khibiny pluton to the central ring structure; and (iii) from the bottom to top
of the differentiated complex in the Lovozero pluton. The results obtained coupled with other geochemical data suggest multistage
generation and transformation of hydrocarbons from the magmatic to the final low-temperature hydrothermal stage. The MWD of
hydrocarbon components in gases occluded by minerals can serve as an indicator of conditions characteristic of rock and ore
formation, as well as of the consecutive formation and transformation of associated minerals revealing ambiguous and controversial
relationships. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|