Semester
Spring
Date of Graduation
2023
Document Type
Thesis
Degree Type
MS
College
Eberly College of Arts and Sciences
Department
Geology and Geography
Committee Chair
Kathleen Benison
Committee Member
Dorothy Vesper
Committee Member
Jaime Toro
Abstract
Ancient acid-saline lakes of the midcontinental United States deposited bedded halite during Permian time. These deposits are not typically preserved at the surface, but drill cores of the Opeche Shale of North Dakota and Cedar Hills Sandstone of Kansas contain preserved beds of halite. Halite from these ancient lakes have primary fluid inclusions that contain Permian lake water. Also included are accidental daughter crystals that were trapped inside the fluid inclusions at time of halite precipitation. Both the fluid and daughter crystals inside bedded halite can tell us about the geochemistry of original lake waters of Pangea.
Petrography and laser Raman spectroscopy were used to investigate the fluids and solids in chevron halite crystals. Petrography was used to find and characterize fluid inclusion and daughter crystal targets. Transmitted, polarized, and UV-vis light sources were used at magnifications ranging from 10x to 2000x. Laser Raman spectroscopy was then used to identify chemistry and daughter crystal mineralogy of fluid-phase and accidental daughter crystals. Bisulfate (HSO4-) and sulfate (SO42-) compounds were detected in fluid-phase; bisulfate that was found in 64% of Opeche Shale fluid inclusions indicate low (
This thesis has application to similar ancient acid-saline lake systems on both Earth and Mars. Petrography and laser Raman spectroscopy were both in-situ and non-destructive methods that could be used on valuable Mars samples brought to earth as part of the Mars Sample Return mission. This study shows that petrography and laser Raman spectroscopy can characterize ancient depositional waters through the analyses of fluids and accidental daughter crystals within primary fluid inclusions.
Recommended Citation
Prchlik, Ryan James, "A study of accidental daughter crystals in fluid inclusions in bedded halite from the Permian Opeche Shale and Cedar Hills Sandstone of the midcontinental United States" (2023). Graduate Theses, Dissertations, and Problem Reports. 11806.
https://researchrepository.wvu.edu/etd/11806