Optimization of a steam-assisted gravity drainage project in the Monarch sands of the south Midway-Sunset field

This report presents several scenarios for oil recovery optimization of Berry Petroleum Company`s properties in the Midway-Sunset field in Kern County, California. The primary goal was to evaluate reservoir performance with a number of vertical wells recompleted in the lower half of the existing oil bank and with a number of horizontal infill wells. Case comparisons and recommendations are based solely on oil production rates and cumulative oil production obtained from the simulations; no economic analyses were performed as part of this study. The results indicate that recompleting two thirds of the vertical wells in the lower half of the existing oil bank will give the most improvement in oil recovery. The models also show that accelerated oil recovery will be obtained from the horizontal well scenario (Case h3), with initial oil rates higher than the vertical well recompletion scenario (Case 3). However, in the long term (11 year period), the cumulative oil production of the horizontal well will fall below that of the vertical well recompletion scheme (Case h3 vs. Case 3). Additionally, a combination of horizontal wells with recompletion of 1/3 of the vertical wells will give a significant improvement in oil recovery (Case h8). We recommend that further studies focus on optimizing the amount of steam injected in horizontal wells, frequency and length of the steam-injection and steam-soak periods, optimal horizontal well spacing, and ideal location of horizontal well in the oil bank. This study used Western Atlas` VIP-THERM numerical simulator to generate the history match and all of the alternative strategies presented in this report. The results presented in this report are based on information and field data provided by Berry Petroleum Company