Date of Award

Summer 6-1-2020

Degree Type

Thesis

Degree Name

Master of Science - Geology

Department

Geology

First Advisor

Julie Bloxson

Second Advisor

R. LaRell Nielson

Third Advisor

Kevin Stafford

Fourth Advisor

Robert Friedfeld

Abstract

Sediment gravity flows into deep-water environments are important stratigraphic traps in lithologically diverse reservoirs generating multiple plays for hydrocarbon exploration. These highly heterogeneous deposits can be studied by utilizing chemostratigraphy and higher-order sequence stratigraphy; being an accurate method for reservoir characterization. Studying these gravity flows along a carbonate platform’s slope can further expand an understanding of the stratigraphy that is filling adjacent basins. The application of elemental analyses can support in identifying mineralogy that impact reservoir quality, especially when conventional testing cannot be applied.

This study utilizes five cores containing the Wolfcamp Formation from the southeastern slope of the Central Basin Platform in northwest Crockett County, Texas. High resolution chemostratigraphy was conducted using X-ray fluorescence along with total organic carbon, X-ray diffraction, and scanning electron microscope at resolutions based on chemofacies defined by hierarchical clustering analyses. Interpretation of chemofacies, mineralogy, organic matter, gravity flows, and sequence cycles is used to evaluate depositional conditions due to periodic glacioeustasy and episodic sea-level fluctuations and tectonic pulses along the carbonate platform margin of the Wolfcamp Formation.

The study area can be divided into eight facies: (1) bioclast packstone to grainstone, (2) porous bioclast packstone to grainstone, (3) lithoclast rudstone to floatstone, (4) bioclast to lithoclast wackestone, (5) mixed carbonate mudstone, (6) mixed siliceous mudstone, (7) clay-rich argillaceous mudstone, and (8) argillaceous-siliceous mudstone. Gravity flows and depositional processes are characterized: (1) slides to slumps, (2) debris flows, (3) turbidity currents, (4) hemiturbiditic plumes, and (5) hemipelagic deposition. Mudstones associated with gravity flows along the slope are organically-rich (4.65% mean TOC) due to the preservation of organic matter from: (1) organic matter supply, (2) rapid burial, and (3) disoxic conditions.

Creative Commons License

Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.

Share

COinS

Tell us how this article helped you.

 
 

To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.