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The development of fracture networks associated with hydraulic fracturing operations are extremely complex multiphysics processes and there is still no accepted methodology for mapping or realistic recreating such fracture networks. This is an issue especially for modeling purposes, as, ideally, an accurate numerical representation, and subsequent numerical model, should be able to honor the trajectory, type, connectivity, and geometric properties of the complex fracture network generated. This research proposes a novel framework capable of conducting fluid flow numerical simulations based on mapped fracture networks induced during hydraulic fracturing laboratory experiments where a shale sample, under true triaxial reservoir stress conditions, is subjected to fluid injection to mimic a single stage open-hole in-situ hydraulic fracture operation. The resulting post-test fracture network of the shale sample is filled with fluorescent dyed epoxy and subsequently imaged. The images are segmented, and individual fractures are classified based on their geometrical characteristics, as parted bedding planes, opened natural fractures, and newly generated hydraulic fractures. The digital fracture network is numerically represented for fluid flow simulation using a dual-porosity model within the finite volume method. In the numerical reconstruction, fractures are implicitly represented in a set of cells with virtual fracture aperture. The properties of each grid cell are assigned based on fracture classification, and flow between grid cells is explicitly assigned based on the connectivity of the grid cells. Findings show faster fluid drainage parallel to bedding planes (horizontal) than in the vertical direction, indicating strong fluid flow anisotropy.

Pearl Jumeira is an artificial offshore land formation located in Jumeira Beach in the Arabian Gulf and is constructed from Dubai-sourced reclaimed sand and locally sourced rockworks. Reclaimed sand was dredged from known borrow pits in Dubai waters. The island will cover approximately 8.3 million square feet of land (fully serviced with all infrastructure requirements) consisting of more than 3.0 million square feet of residential villa plots and over 90,000 square feet of retail, community, and educational facilities. The current paper presents a geotechnical case study on this reclaimed island in terms of: The geotechnical design, the construction stages, and the ground investigation results. In the geotechnical design stage, soil properties of the reclaimed land were investigated to achieve the design bearing capacity and to assess the risk of liquefaction. In the geotechnical construction stage, soil improvement technologies such as vibro compaction and surface compaction were used. In the soil investigation stage, a set of soil tests were conducted in order to achieve the geotechnical design. These tests include Standard Penetration Test (SPT), Unconfined Compressive Strength Test (UCS), Piezocone Penetration Tests (CPTU), Zone Load Test, Particle Size Distribution (Sieve Analysis), etc.... The thickness of the reclamation fill varies across the site but is typically in the order of 10 m to 15 m and consists primarily of clean sand with lenses of silty materials. The materials below the pre-reclamation seabed comprise of layers of sand and silty materials of varying thicknesses, underlain by the Calcisiltite/Calcarenite bedrock between -10 m and -15 m Dubai Municipality Datum (DMD).

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The Montney Formation of the Western Canadian Sedimentary Basin has emerged as one of the most prolific unconventional resource plays in the North American unconventional space. The authors propose a novel method to better understand the failure mechanics associated with hydraulic fracturing through laboratory testing under true triaxial conditions. This adds essential fundamentals with respect to upscaled field hydraulic fracturing operations in the formation. A representative source rock block recovered from outcrop was prepared into a cube and hydraulically fractured in the laboratory under true triaxial stress conditions. Field outcrop mapping of this quarry has confirmed that samples collected are of the same geological time and spatially equivalent to the source rock (Zelazny et al. 2018). This novel laboratory experiment mimics a single stage open hole hydraulic fracturing using a slickwater system, composed of surfactant, friction reducer, and biocide as the injection fluid. Micro-computed tomography (μCT) scans were used to identify the presence of preexisting fractures and bedding planes. A mini-well was drilled to the center of the cube, parallel to the direction of the minimum principal stress (σ3) and along the strike of the bedding planes, such that there is a 5 mm long down-hole open cavity. The existing true triaxial test system at the University of Toronto was retrofitted to accommodate a custom designed mini-packer system. Stresses were applied hydrostatically, and then differentially until the stress regime, replicating the field observed reservoir depth at about 2 km depth, was reached. The bottom hole was subsequently pressurized by pumping the injection fluid through the mini-packer. The test was numerically modeled in three-dimensions using the hybrid finite-discrete element method (FDEM) with the mechanical properties input determined through a series of standard laboratory rock mechanics tests discussed within. Post-test μCT of the tested cube revealed a fracture trace, and scan contrast was enhanced by injecting the cube with 5% wt potassium iodide solution. Interestingly, the highest fluid pressure recorded is slightly higher than σ3 whilst the plane of failure is normal to the intermediate principal stress (σ2) direction, which is parallel to the bedding planes. The results of the mechanical tests and hydraulic fracturing under true triaxial stress conditions reveal the significance and dominance of the macroscopic features and material anisotropy in dictating the overall strength and fracture plane orientation. Features which were unaccounted for in classical reservoir mechanics and the numerical model simulation, resulted in higher than predicted fracture initiation and propagation pressures than the laboratory experiment. This laboratory test approach allows a convenient and flexible method to capture the influence of the reservoir stress regime and its interaction with the sample anisotropy. Coupled with numerical simulations that encompass such features, this framework can benefit the industry by reproducing typical behavior observed in the field; thus, enhancing, improving, and increasing the efficiency of hydrocarbon recovery.