Due to directions from the City of Tyler and the CDC on COVID 19, this meeting is cancelled.
APRIL 2020 LUNCHEON MEETING
Alex P. Blizzard
presents
Chemostratigraphy of Carbonate Gravity Flows of the Wolfcamp Formation in Crockett County, Midland Basin, Texas
11:30 AM Wednesday, April 15, 2020
at the Cascades
4511 Briarwood Road
Tyler, TX 75709
Cost: $25
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 explored by combining 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 on the stratigraphy that is filling adjacent basins. The application of elemental analysis 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 analysis. Interpretation of chemofacies mineralogy and 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 and 8.7% highest TOC) due to the preservation of organic matter of organic supply from: (1) high productivity, (2) rapid burial from high sedimentation rate, and (3) disoxic conditions from slide to slump paleotopographic restriction. These slope deposits could potentially be an unconventional play by targeting these organic rich mudstones or associated tight carbonates.
BIOGRAPHY
Alex P. Blizzard is a graduate student at Stephen F. Austin State University. He received his B.S. degree in geology from Texas Tech University in 2018, and is graduating with his M.S. in geology from Stephen F. Austin State University in August 2020. Alex has worked with various companies including Tanos Exploration, Inspiration Energy, and Daylight Petroleum throughout his graduate school. He will be interning with Chevron’s Midcontinent Business Unit this summer in Houston. His contact information is email: blizzardap@jacks.sfasu.edu, telephone: 214-862-0989.
