DEVELOPMENT OF THE WILCOX SAND: COWETA OIL FIELDS - WAGONER COUNTY, OKLAHOMA
This shallow conventional oil play has been producing oil for several decades. Millions of barrels of oil have been produced from the Coweta Oil Field in multiple zones. These zones include Dutcher Sandstone, Pink Lime, Mississippi Limestone, Wilcox Sandstone, and the Tyner Sandstone.
Numerous multi-million barrel reservoirs in the Wilcox Sand are left to be developed and put into production. Technology to produce the Wilcox sand was not economically available until recently. The Wilcox Sandstone reservoir tops at 900 to 1000 feet deep and is consistently 30 to 42 feet thick. These wells are relatively shallow, simple, and easy to drill. Most of the necessary drilling and completion technology is available locally, and has been in use for decades so the drilling and completion costs for these wells are relatively low and predictable. This prospect is on a 40-acre tract of land surrounded by both currently producing and previously producing oil & gas wells. The thirty eight control wells that were drilled on and around Tract 1 produced oil or gas from at least one zone other than the Wilcox.
Since 1922 numerous oil men and oil companies; including Getty, Phillips 66, and Gulf have drilled with the anticipation to produce the Wilcox reservoir which was discovered in 1918. Each and every well was successful in hitting the Wilcox formation and starting initial production. The wells made an enormous quantity of oil during initial production. However, when the wells were put on, pump scaling began to occur. The scaling would reduce production in 30 to 60 days to a point where pulling the production string was required to remove the scale. Records indicate that each producer used the current technology of the time to combat the scale, but there really was no solution for suspending the scale. With these kind of results on record, at the Mid Continent Oil Library, the field was largely ignored until recently.
In the past six months, Mark Resources purchased 3 Wilcox wells drilled in 1995. These wells had very limited production due to the barium sulfate scale. In April of 2012 Mark Oil reworked the production equipment, cleaned the wells, and started production. Petrolite was contracted to start a treatment program on the 3 wells - using the same chemicals and process used in this project. The production, in a 90 day time period, has gone from 11 barrels a day to over 30 barrels a day as the wells continue to clean out with the treatment. The full potential of the wells is not expected to be obtained until late September 2013.
The chemical used in treating the Wilcox production to suspend the barium sulfate is Petrolite SCW2600. SCW2600 scale preventative is an aminomethylene phosphonic acid scale inhibitor which was developed especially for use in controlling barium sulfate scaling. It is an excellent inhibitor for control of calcium carbonate deposition, and is also useful in inhibiting calcium sulfate deposition.
The primary production formation in this project is the Wilcox Sand. Completion reports, on file in the Oklahoma Corporation Commission, show the Wilcox in this prospect location to be thicker than most Wilcox deposits producing in Oklahoma. The Wilcox is a beach sand, or blanket sand deposit and fairly even when it is present. Using the records on file, an Isopach model was developed for this project. It shows that the Wilcox producing section is 30 to 42 feet thick and pretty consistent across the quarter at that thickness. It is that thickness that accounts for the initial production reports of 300 plus barrels a day production.
FAIR WIND CAPITAL, LLC
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