Montana Tech Library Digital Commons @ Montana Tech Graduate Theses & Non-Theses Student Scholarship Spring 2018 FLUID INCLUSION AND STABLE ISOTOPE INVESTIGATION OF HYDROTHERMAL TALC AND CHLORITE DEPOSITS IN SOUTHWEST MONTANA Garrett iH ll Montana Tech Follow this and additional works at: https://digitalcommons.mtech.edu/grad_rsch Part of the Geological Engineering Commons Recommended Citation Hill, Garrett, "FLUID INCLUSION AND STABLE ISOTOPE INVESTIGATION OF HYDROTHERMAL TALC AND CHLORITE DEPOSITS IN SOUTHWEST MONTANA" (2018). Graduate Theses & Non-Theses. 164. https://digitalcommons.mtech.edu/grad_rsch/164 This Thesis is brought to you for free and open access by the Student Scholarship at Digital Commons @ Montana Tech. It has been accepted for inclusion in Graduate Theses & Non-Theses by an authorized administrator of Digital Commons @ Montana Tech. For more information, please contact
[email protected]. FLUID INCLUSION AND STABLE ISOTOPE INVESTIGATION OF HYDROTHERMAL TALC AND CHLORITE DEPOSITS IN SOUTHWEST MONTANA by Garrett Hill A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Geoscience Geology Option Montana Tech 2018 ii Abstract Talc and chlorite deposits of southwest Montana formed as hydrothermal replacements of Archean and/or early Proterozoic dolomitic marble and quartzo-feldspathic gneiss. Although the hydrothermal replacement model is generally accepted, less is known about the temperature, composition, and origin of the fluids involved in talc and chlorite formation. The present study examines fluid inclusions in quartz associated with both talc and chlorite, stable hydrogen and oxygen isotopes of talc, chlorite, and quartz, and stable carbon and oxygen isotopes of carbonate minerals. The deposits being examined include the Yellowstone, Beaverhead and Willow Creek talc mines, and the Antler chlorite mine.