Diagenesis And Controls On Porosity And Permeability In The Upper San Andres Formation Of West Texas
Date of Award
8-2025
Degree Type
Thesis
Degree Name
Master of Science - Geology
Department
Geology
First Advisor
Dr. Julie Bloxson
Second Advisor
Dr. R. LaRell Nielson
Third Advisor
Dr. Zachariah Fleming
Fourth Advisor
Dr. Jenny Rashall
Abstract
West Texas reservoirs on the Central Basin Platform (CBP) are dominated by Permian-age carbonate deposits, significantly contributing to petroleum production. The Upper Permian-aged San Andres Formation, composed primarily of dolomite and limestone, is a prolific reservoir. This study assesses diagenetic influences on porosity and permeability within the San Andres Formation along the northern CBP. Two cores from the Monument 4-2 and Peterson 1 wells in West Texas were analyzed using core descriptions, thin section petrography, XRD, XRF, and MICP. Results indicate that dolomitization enhances porosity, with intercrystalline and moldic porosity being dominant, while late-stage cementation and compaction reduce permeability. XRD reveals variations in clay and dolomite content correlating with reservoir quality, and XRF data highlight elemental trends associated with diagenetic changes. MICP data suggest that pore throat size distribution varies with mineralogical changes, influencing reservoir connectivity. The study concludes that reservoir quality is primarily controlled by diagenetic overprinting, including dolomitization, dissolution, and cementation.
Repository Citation
Butcher, Jack, "Diagenesis And Controls On Porosity And Permeability In The Upper San Andres Formation Of West Texas" (2025). Electronic Theses and Dissertations. 599.
https://scholarworks.sfasu.edu/etds/599
Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.
