Channel Fracturing - A Paradigm Shift in Tight Gas Stimulation

Abstract

The hydraulic Channel Fracturing technique relies on the engineered creation of a network of open channels within the proppant pack, which provides for highly conductive paths for the flow of fluids from the reservoir to the wellbore. This paper provides a comprehensive summary of the implementation of this technique in ultra-low permeability, gas-bearing formations. The Lance formation in the Jonah field near Pinedale, Wyoming was selected for this study. This formation comprises fluvial sand bodies with 0.0005 to 0.05 mD permeability and 35 to 55% gas saturation. The formation requires hydraulic fracturing for economic production. Key historical issues for the stimulation of this formation using gelled fluids and sand as proppant are limited fluid recovery and consequential formation and fracture conductivity impairments. Slick-water treatments have rendered moderate gains in production mainly in low-prospect zones with some occurrence of near-wellbore screen-outs. Moderate increases in production from using ceramic proppants have been gained at the expense of significant increase in stimulation costs. Hydrocarbon production, treating pressure and fracturing fluid recovery data from a thirteen-well campaign in the Jonah field are summarized in the manuscript. Results indicate that the implementation of the channel fracturing technique increased initial gas production and estimated recovery over conventional fracturing methodologies. Positive features that were also observed during this campaign such as reduced net pressure increase estimates from pre- and post-frac shut-in pressure measurements, reduced tendency for vertical fracture growth and elimination of near-wellbore screen-outs are also reported and discussed. It is concluded that the Channel Fracturing technique is a viable alternative to conventional fracturing methods for more efficient and effective stimulation of complex tight gas formations.

Experimental Research on the Proppant Transport Behavior in Nonviscous and Viscous Fluids

“…Currently, the single-wing transparent parallel plates experimental devices used at the University of Texas, University of Alberta, University of California, China University of petroleum, Southwest Petroleum University, BJ Service Company, Sinopec Research Institute, and others − do not demonstrate a big difference compared with Kern’s and Babcock’s apparatuses, except for some improvements on the fracture wall and entrance. For the design of fracture entrance, Tong et al injected fluid from the top of the slot by gravity, Alderman and Wendorff and Brannon et al used a trumpet-shaped inlet to distribute fluid and pressure more evenly in the fracture; these two types of entrances did not take the influence of perforations into account.…”

A composite dual-porosity fractal model for channel-fractured horizontal wells

“…As a result of heterogeneous distribution of fracturing proppants, the channel-fracturing technique could provide fracture conductivity that is several folds larger with proppant-free conduit fractures than that of conventional continuous placement of proppant (Yudin et al, 2012). In the past three years channel fracturing treatments have been applied in over 1000 wells in the Loma La Lata field, Argentina (Gillard et al, 2010), Vaca Muerra Shale, Neuquen (Ejofodomi, Cavazzoli, Morris, & Prioul, 2014), the Taylakovskoe Oil Field Stud Horse Buttle (Johnson et al, 2011), Abu Roach, Egypt and Eagle Ford Shale (Inyang, Nguyen, & Cortez, 2014). Channel fracturing has been proven to both enhance production and be more economical (Altman et al, 2012).…”

Effect of fiber on the rheological property of fracturing fluid

“…Fiber is often used in hydraulic fracturing, such as channel fracturing (Ejofodomi et al, 2014;Gillard et al, 2010;Johnson et al, 2011;Medvedev et al, 2013;Rhine et al, 2011) and FiberFRAC (Bulova et al, 2006;Engels et al, 2004;Guo et al, 2012;Vasudevan et al, 2001), to enhance the proppant carrying capacity of fracturing fluid and to prevent the dispersion of proppant-laden pulses, thus decreasing the settling velocity of proppant and transporting proppant farther within the fracture. According to statistics of Schlumberger Company, more than 24,000 stages channel fracturing treatments have been performed in shale-, carbonate-, and sandstone-rich reservoirs during the last four years in over 20 countries.…”