The Influence of Subsurface Conditions on Hydraulically Induced Fractures in Deep Rocks

Abou-Sayed, Ahmed S.
Presented at Hydraulic Fracturing and Geothermal energy, Prceedings of the First Japan-United States Joint Seminar on Hydraulic Frcturing and Geothermal Energy, Tokyo, Japan, November 2-5, 1982, pp 125-143


A discussion is presented on the influence of subsurface conditions such as, stress,rock properties and pre-existing geologic structures on the shape and azimuth of hydraulically induced fractures in deep rocks. A systematic approach to optimum fracture design would require a combined field, laboratory and analytical effort to determine these conditions. Detailed field testing involves in situ stress measurements, fracture orientation determination and monitoring of flow rate and bottom hole pressure during the stimulation treatment. Laboratory tests would provide the mechanical and physical properties of the rock as well as its sensitivity to interaction with its pore fluid and the fracturing fluids used in the treatment. All information is to be synthesized into the fracture design utilizing computer simulators.