Azimuth control of hydraulic vertical fractures in unconsolidated and weakly cemented soils and sediments

摘要

The invention is a method and apparatus for initiating an azimuth controlled vertical hydraulic fracture in unconsolidated and weakly cemented soils and sediments using active resistivity to monitor and control the fracture initiation and propagation. Separate or overlapping treatment walls and containment barriers can be created by controlling and monitoring the propagation of fractures in the subsurface. A fracture fluid is injected into a well bore to initiate and propagate a vertical azimuth controlled fracture. The fracture fluid is energized to conduct electrical current while the fracture propagates through the ground. A series of electrical resistivity monitors measure the electrical conductivity of the fracture fluid in real time against the background conductivity of the formation. Using a series of incremental influence functions, the azimuth of the vertical fracture can be controlled by regulating the injection of fracture fluid based upon the induced voltage of the earth and the conductivity of the fluid in the fracture. IMAGE