Characterization and Production Influence of Geological Facies in the Eagle Ford
- Bhaskar Sarmah (Halliburton) | Nicholas Garrison (Halliburton) | Eli Bogle (Halliburton) | Katie Ross (SM Energy Company) | Patrick Noon (SM Energy Company)
- Document ID
- Society of Petrophysicists and Well-Log Analysts
- SPWLA 60th Annual Logging Symposium, 15-19 June, The Woodlands, Texas, USA
- Publication Date
- Document Type
- Conference Paper
- 2019. held jointly by the Society of Petrophysicists and Well Log Analysts (SPWLA) and the submitting authors
- 10 in the last 30 days
- 124 since 2007
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The purpose of this study was to correlate subtle changes in reservoir quality to production. The groundwork was provided by unique lessons arising from core and log analyses, including machine learning, to identify target facies within the reservoir and stage level production logs provided by permanent fiber optic cable. Production results on a stage level produced by fiber optics provided insight into production drivers. These lessons were then applied to fracture and reservoir models.
The workflow began by categorizing unique facies within the Eagle Ford shale with the help of a selforganizing map model. Wireline log variables, such as gamma ray, neutron porosity, bulk density, deep resistivity, and compressional slowness, were used to discern different facies within the Eagle Ford shale. These log facies demonstrated an excellent match with whole core-derived facies, which took into account mineral volumetric compositional variation, carbonate grain-size variation, and kerogen content. Before completing the study well, a cased hole logging suite was run, and the facies were identified along the lateral. Permanent fiber optic cable was installed on the backside of the casing to observe completions and production trends along the lateral. Experiments performed throughout the completions included varying rate and perforation design, use of chemical diversion and acid, and pump schedules. Fluid and proppant per lateral foot were held constant throughout the lateral. Calibrated fracture and reservoir models were then built around the observed completion effectiveness and initial production results of each stage.
Despite the changes in completion design, the only solid correlation in initial production is the facies identified along the lateral. The best producing facies were those with the highest porosity and organic content. Although a modeled fracture height exceeded 50 ft, the reservoir quality immediately adjacent to the wellbore was the largest determining factor in initial production. The strong correlation between these facies led to further investigation between production mechanisms and reservoir quality. Current trends to improve unconventional completions include increased perforated clusters, pounds of proppant, and gallons of fluid per lateral foot. However, reservoir understanding and quality lateral landing targets cannot solely be replaced by larger completions.
|File Size||2 MB||Number of Pages||12|