For operators who have established a core development area, drilled their wells out and have been experimenting with bigger frac jobs, what’s left? While longer wells drilled in the best rock with the biggest fracs may have the highest rates, our industry will keep pushing the limits of completions.
An increasingly popular technique in US shale plays that has recently been adopted by some operators in the Duvernay and Montney is “extreme limited entry” (XLE) fracturing and the more targeted “aggressive limited entry” (ALE). In these completions, the frac job is pumped through a very small number of perforations, resulting in a high pressure drop (ΔPpf) across each perforation during the frac which helps to ensure each perforation receives high volumes of fluid. This assists with frac initiation, reduction of near wellbore tortuosity, better chance of proppant transport, and helps to establish a more uniform fracture growth along the wellbore. In short, XLE and ALE offer the possibility of higher cluster efficiency during multi-cluster plug-perf completions.
Utilizing GLJ’s extensive completion database, we can utilize high measurements of ΔPpf as a proxy for application of XLE technology (ΔPpf ≈ 15-20 MPa). If we consider higher rates to be indicative of better well performance, logic dictates that if higher rates are observed with higher ΔPpf, XLE — that’s a good thing. In the plots below, we can compare the results of increased ΔPpf on initial gas rates for gas wells (left) and oil rates (right).