Hydraulic fracturing technique - with multiple fracturing cycles using fine-sized and then medium-sized proppant

摘要

The hydraulic fracturing of subterranean formations comprises using multiple fracturing cycles to generate vertical linear fractures or linearly extending fractures outward from the point of introduction of the fracturing fluid. The method involves introducing into the formation a series of slugs of proppant-carrying fracturing fluid carrying fine-sized proppant in amts. of =5 lbs/gal., with proppant-free spaces slugs being introduced between the stages. Both fracturing fluid and spaces are injected at rates of 25 bbl/min., and injection is continued until =25000 lbs. fine-sized proppant have been deposited in the formation per each foot of available net producing interval. The formation of radial vertical fractures is eliminated. The linear fractures created are much wider than those made by prior art methods, and considerably higher amts. of proppant are deposited.