Physical Sciences and Mathematics Commons^™

Pedogenic Relationships In A Texas Vertisol Climosequence Defined By Geochemical Mass Balance Of Whole Soil And Chemistry Of Iron-Manganese Nodules, Cynthia A. Stiles

Doctoral Dissertations

Climosequence Vertisol profiles derived from the Upper Beaumont Formation in the Gulf Coastal Prairie physiographic province of Texas were examined for geochemical trends ascribed to different precipitation regimes. Mass-balance relationships were utilized for the comparisons. Compositional differences in zirconium (Zr) content between the solum and lower sub-soil precluded it use an immobile strain (volumetric change) indicator. This difference was correlated to sand weight percent (r² = 0.65**). Titanium (Ti) content did not shift correlatively with depth, thus making Ti the preferred strain index element for mass-balance calculations. Depths at which the Zr compositions shifted were not directly related to …

Diagenesis Of Upper Cambrian Mount Simon Sandstone In The Illinois Basin - Microscale Investigation Of Basinal Fluid Migration And Mass Transfer, Zhensheng Chen

Doctoral Dissertations

A series of investigations were conducted to evaluate microscale evidence for basinal fluid migration in the Illinois basin during diagenesis of the Upper Cambrian Mount Simon Sandstone. Samples were examined using transmitted light and cathodoluminescence (CL) petrography, fluid inclusion analysis, and Secondary Ion Mass Spectrometry (SIMS) analysis of ¹⁸O/¹⁶O ratios and trace element compositions. Preliminary investigation of in situ laser ablation ⁴⁰Ar-³⁹Ar age dating techniques on authigenic K-feldspar over growths was also completed.

Two major generations of quartz overgrowths are observed, on the basis of transmitted light and CL petrography and fluid inclusion studies. …