Geothermobarometry and Petrographic Interpretations of Christensen Ranch Meta- Banded Iron Formation from the Ruby Range, Montana
Year: 2015
Type: dissertation
Abstract: The Ruby Range in southwestern Montana was tectonically uplifted during the mountain-building event of the Big Sky orogeny. Contained within the Christensen Ranch Formation, made up of sedimentary units metamorphosed during the Big Sky orogeny, are a small number of metamorphosed banded iron formations (BIFs). It is the presence and composition of these BIFs which is the focus of this research, principally their depositional origin, relationship to surrounding sedimentary packages, elemental and mineral compositions, and lastly, peak metamorphic conditions. Samples were collected, cut into thin sections, and powdered for textural and compositional analyses employing polarized light microscopy, Raman microscopy, scanning electron microscopy, X-ray diffraction and electron microprobe analyses. Mineral phase assemblages and compositional data suggest differences in protoliths between Stone Creek and Iron mine metamorphosed BIFs in addition to greater activity of fluid phases during the metamorphism of Iron Mine formations.
Author: Jacob Hughes
Institution: Western Kentucky University
Language: English
Subfield: Geochemistry and Petrology
Field: Earth and Planetary Sciences
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W257051711