Raman spectroscopy of organic, solid and fluid inclusions in the Oldest Halite of LGOM area (SW Poland)

Spectrochim Acta A Mol Biomol Spectrosc. 2018 Jan 15:189:381-392. doi: 10.1016/j.saa.2017.08.024. Epub 2017 Aug 12.

Abstract

Raman spectroscopy was applied to determine the degree of recrystallization and the influence of the secondary solution migration on the Oldest Halite (Na1) in Lubin-Głogów Copper District (LGOM). Numerous organic matter (OM) inclusions which generally show weak structural ordering was found in halite crystals. In this context they are similar to solid bitumens or carbonaceous matter of low thermal alteration. The difference in the Raman line-shape of OM indicated various thermal alteration of salt from the Oldest Halite formation due to hot fluid flow. Solutions included in the secondary fluid inclusions often contain dissolved gases such as CH4, N2, H2S. The presence of these gases is connected with migration process from basement to the salt formation. Moissanite in fluid inclusions was accidentally trapped during inclusion formation, i.e. is not a daughter mineral. It was also found in the halite as an individual solid inclusions as well as in the anhydrite concentrations. Raman spectroscopy allowed to determine also such solid inclusions in halite as celestine, magnesite, pyrite, lepidocrocite and goethite as well as hydrocarbons.

Keywords: Halite recrystallization; Moissanite; Raman spectroscopy; Rock salt; Secondary migration.