Evaluating Multiple Fractured Cased Hole Completion Performance for Gas Wells in the Upper and the Lower Montney Formation, Canada

Abstract

Abstract The Lower Triassic Montney Formation produces from the Western Canadian Sedimentary Basin. This shale play is extensive as it covers nearly 57,000 square miles. The play consists of landing intervals in the Lower, Middle, and Upper Montney Formation for which the oil and gas industry uses multiple fractured horizontal well completions to recover natural gas. Both cased and open hole completions are utilized in the Montney Formation. Identifying the key drivers for success of multiple fractured horizontal wells is not straightforward, especially in unconventional reservoirs like the Montney. One study by Christie et al investigated the completion trends of four Montney operators since 2005 and showed the average completion interval length, the average number of fracture stages, and the volume of proppant used per fracture all increased over time. Al-Alwani et al, provided a statistical analysis of both open and cased hole Montney completions based on publically available data. The authors showed that for the entire well population, cumulative gas recovery per stage declines as the number of completed stages increased. It was also shown that cased hole wells performed much better than open hole wells although the completion costs were at least 50% greater. However, this statistical analysis did not differentiate between completions in the Upper, Middle, or Lower Montney nor did it include perforation cluster data. This work documents the statistical analysis of 296 cased-hole horizontal gas well completions in the Upper and Lower Montney. The work extends the previous statistical study of Montney completions by focusing on cased hole completions, including completion cluster information, and examining the performance of Upper and Lower Montney completions separately. Results of this analysis show that cumulative gas production per cluster decreases as more perforation clusters are placed in both the Upper and Lower Montney. The study demonstrates that the cumulative gas production per cluster and initial gas production (IP) is higher for the Upper Montney Formation than the Lower Montney Formation. This work benefits the industry by: Providing a more focused statistical analysis of horizontal gas well cased hole completion performance in the Montney, compared to recent literature documenting industry practices. Identifying a maximum recommended liquid per cluster amount for completions in the Montney Formation. Providing a comparison of Upper and Lower Montney cased hole completion performance.