Channel fracturing combines geomechanical modeling, intermittent proppant pumping and degradable fibers and fluids to attain heterogeneous placement of proppant within a hydraulic fracture. The aim of this well stimulation technique is to promote the formation of stable voids or streaks within the proppant pack which serve as highly conductive channels for transport of oil and gas throughout the hydraulic fracture.More than 10,000 channel fracturing treatments have been performed in over 1,000 wells during the last three years in shale-, carbonate-, and sandstone-rich reservoirs worldwide. The collective dataset on job execution and well performance shows the following trends: (a) low occurrence of near wellbore screen-outs (>99.9% of all treatments achieving 100% proppant placement); (b) reduction in the amount of proppant required to complete treatments (in average, 43% less proppant than conventional techniques aiming at placing a homogeneous proppant pack as implemented in offset wells); (c) average initial and long-term well productivity and flowing pressures consistently meeting or exceeding those of wells completed with conventional fracturing techniques. This paper summarizes findings from a comprehensive technical study focused on ascertaining the enabling mechanisms for these trends. Results from laboratory experiments (large-scale slot flow, conductivity, proppant settling), yard tests (well site delivery characteristics, proppant slug integrity), and well performance evaluations (surface treatment data, well production data and reservoir simulations supported by history matching) are analyzed collectively to reach the following assessments: (a) heterogeneous proppant placement is achieved; (b) the low incidence of screen-outs is the result of the combination of reduced usage of proppant and intermittent pumping of proppant-free, fiber-laden slugs ("sweeps") which mitigate accumulation of proppant in the near-wellbore area; (c) well productivity trends are driven by the concomitant occurrence of enhanced fracture conductivity -enabled by the presence of heterogeneities within the proppant pack-and the development of larger fractured area within the reservoir effectively contributing to production. The development of larger effective contact area is enabled by the use of fibers, which enhance proppant transport within the fracture and mitigate proppant settling.

This paper describes the application for the first time of a novel channel fracturing technique combined with rod-shaped proppant in selected production targets in several fields in the Egyptian western desert. The channel fracturing technique introduces channels within the proppant pack that increase conductivity and effective half-length leading to increased productivity (Gillard et al. 2010). Rod-shaped proppant when used as tail-in in fracturing treatments increases near-wellbore fracture conductivity and prevents proppant flowback due to its particular geometry (McDaniel et al. 2010).The western desert fields in the Qarun concession area in Egypt are characterized as complex, thin-bedded sequences with heterogeneous laminated sandstones producing mainly from the Abu Roash and Upper Bahariya formations. Hydraulic fracturing has traditionally been employed to produce hydrocarbons from these marginal reservoirs. The channel-fracturing technique was first introduced in the Amana fields in late 2012 combined with rod-shaped proppant for flowback control and conductivity enhancement. Early-time normalized production of the wells fractured with this technique increased by 89% over offset wells fractured conventionally, and the application of the channel fracturing technique eliminated the incidence of premature screen-outs in all fields.The positive results from implementation of this combined stimulation technique have led to a vigorous expansion of its utilization throughout Egypt's western desert area, including a refracturing campaign for older wells where conventional fracturing techniques did not yield the desired results.

In multistage fracturing of unconventional formations such as the Eagle Ford shale, wells are traditionally stimulated by fracturing several perforation clusters simultaneously. While the technique is operationally efficient, there is evidence from production logs, microseismic monitoring, and other measurements that several clusters produce below expectations or do not produce at all. This condition is to a degree because stages penetrate zones with stress heterogeneities, and consequently, fractures propagate unevenly from all of the clusters. Evenly fracturing all clusters in heterogeneous zones is challenging in long horizontal sections penetrating heterogeneous reservoirs. Furthermore, efforts to improve well economics result in reducing completion time by extending the length of each stage even further to decrease the number of interventions required for completing the well. To address this challenge, a new sequenced fracturing technique has been developed based on a novel composite fluid comprising of degradable fibers and multi-sized particles that diverts the remaining stimulation fluids to understimulated regions of the wellbore. The composite fluid is delivered downhole at high-concentration, to create temporary plugs in clusters already stimulated thereby creating diversion with a minor amount of material. The solids degrade completely after the fracturing treatment has been completed, leaving no residual formation or fracture conductivity damage. The channel fracturing technique (Gillard et al. 2010) was chosen as the preferred fracturing method for use in tandem with the composite fluid. This technique has been reported to increase effective fracture length while reducing risk of screenout with respect to other conventional methods. The new composite fluid was used in a campaign where its effects were monitored with microseismic instruments. A case study presents field experiments where wells from the same pad are fractured in a similar fashion with and without diversion. In one application, with similar water and fluid volumes, the well treated with this technique produced more than 15% per stage than its conventionally treated offset well. The signature of the composite fluid, clearly visible on all measurement techniques, has proven consistent across stages of various lengths and wells having different characteristics.

The Western Desert of Egypt is a mature hydrocarbon province that has been producing oil and gas for the past 60 years. With the vast majority of the oilfields in decline, almost all wells require hydraulic fracture stimulation to produce economically. This paper describes the application for the first time of a novel channel-fracturing technique combined with rod-shaped proppant in selected production targets in the Cretaceous-aged Abu Roash and Upper Bahariya formations in the El-Fayoum concession in the Egyptian Western Desert. The channel fracturing technique introduces channels within the proppant pack that increase conductivity and effective half-length leading to increased production (Gillard et al. 2010). Rod-shaped proppant when used as tail-in in fracturing treatments increases near-wellbore fracture conductivity and prevents proppant flowback due to its particular geometry (McDaniel et al. 2010). Many sedimentary features of hydrocarbons in the Western Desert in Egypt are characterized as multi-layered, deltaic, thinly and tightly laminated sandstones consisting of sands with limited lateral and vertical extension with an average permeability of 1 mD and Young's modulus in the order of 2.6 million psi. Historical challenges in the field using conventional hydraulic fracturing have included a premature screen-out rate greater than 45% and subsequently, proppant flowback issues. A campaign of 4 wells was conducted in the Silah field in the El-Fayoum concession for comparison against 7 offset wells fractured with conventional techniques. With the application of the channel fracturing technique, the screen-out rate of fracturing treatments was reduced to zero, thus eliminating the cost of additional workover rig time or coil tubing cleanup time, and in most cases, the loss of a potentially productive zone. Further, the application of rod-shaped proppant has eliminated proppant flowback. The positive results from implementation of this combined stimulation technique have led to a vigorous expansion of its utilization throughout Egypt's Western Desert area.