The Potential of Multiple Fractured Horizontal Wells in Siberian Oil Fields

This reference is for an abstract only. A full paper was not submitted for this conference. Many of the Western Siberia oil fields are being developed/exploited with hydraulically fractured S-shaped wells (vertical through the pay section).Horizontal wells are also used; however, in many of the fields these wells are out performed by the vertical fractured wells. The reasons for this appear to be poor vertical permeability and sub-optimal drilling and completions practices. To better quantify the potential of an undeveloped area of a western Siberian oil field, five different well types were evaluated: Vertical, Vertical-Fractured, Slanted (80 deg crossing multiple layers), Horizontal (with a single layer), and Multiple-Fractured Horizontal wells. These well completion types were evaluated using a reservoir simulation model of a sector of the field. The results of this analysis demonstrated that the multiple fracture horizontal well completions outperform the other well types and that they can have a substantial positive impact on the economics of the field development. With traditional fracturing and completion techniques, where packers or bridge plugs are used to provide zonal isolation, fracturing horizontal wells is a complex operation with increased risk and not always economical. New pin-point fracturing techniques can eliminate many of these problems and reduce risk. Recent developments in these technologies make it possible to perform the same type of aggressive frac jobs as currently performed in vertical wells, with large proppant volumes and large proppant sizes (12/18), at multiple selected locations along a lateral wellbore. To realize the full potential of this type of completion plan, traditional thinking, regulatory barriers, and equipment limitations need to be overcome. This process has started, and some operators are currently planning trial multiple fractured horizontal wells to demonstrate the potential. This paper illustrates the potential demonstrated by the development study and recent technology developments that will allow the placement of multiple fracs in horizontal wellbores and the practical aspects that need to be addressed for operators to fully capture the potential. A number of operators have firm plans to perform such fracs in horizontal wells. If performed in time, approval will be sought to present case histories in this paper.