Abstract
Polymer gels used for shutting off unwanted water in producing oil wells are certainly no stranger to the Arbuckle dolomite formation in Kansas, but in years past, they have delivered short-lived results and have been only marginally successful. In November 1997, that all changed after a unique design strategy utilizing proven polymer gel technology caused dramatic increases in oil production that resulted from shutting off a significant volume of water from a well located in the Bemis-Shutts field. Since that time, more than 200 wells have been treated for about 35 different operators with a greater than 95% success rate. Thousands of barrels of incremental oil at each treated well are being realized, and hundreds of thousands to millions of barrels less water are being produced from each treated well, than otherwise would have been produced without the treatment. These treatments are extending, by several years, the economic life of many Arbuckle wells, and are bringing shut-in wells back to life.
This paper will report lessons learned from applying polymer gel water shut off technology to the Arbuckle formation, and present statistical data derived from a detailed database that has been maintained throughout the project. In addition to using the database as a tool to quantify results and further improve job performance, it is also being used to improve the predictability of response to treatment. Post-treatment oil and water production performance and treatment longevity will be compared to several variables like polymer gel treatment volume and injection pressure. The paper will also discuss how polymer injectivity and post-treatment well performance changes from place to place within the Arbuckle formation. Finally, treatment economics including job cost, payout time, revenue gain from increased oil and decreased water production, and return on investment will be presented.
