Numerous proppants, additives and remedial treatments now exist for the control of proppant flowback, yet it continues to be a problem in many oil and gas wells. These approaches to the problem can have certain merits but as a general rule they negatively impact production and are more costly than proppant alone. The improtance of these criteria must be balanced against the effectiveness of the chosen approach. It has been observed in laboratory testing that a deformable proppant material, blended with a typical fracturing proppant, can significantly increase a proppant pack's resistance to failure under flowing conditions. The fluid exerts a drag force on the structure of the pack and indeed on the individual particles within. These drag forces appear to be much less than the overburden forces that maintain a proppant pack in a stable configuration, prior to fluid flow. In essence proppant packs of typical fracture width. when tested in the laboratory are inherently unstable, unless the individual particles within are anchored or reinforced in some way. When a deformable proppant is blended into the pack. the deformation between the surrounding proppant grains allows locking of these grains in place. The friction between the grains is effectively increased and thus, the forces required to push the material out of the structure also increase. Addition of deformable particles typically allows the drag forces at failure to be increased by 100
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