Understanding the geometry of a hydraulic fracture is key to predicting its behavior and performance. Physical measurement of field hydraulic fracture geometries beyond the borehole is difficult and typically cost prohibitive with the only published examples being mine-back studies and cores. Laboratory-scale hydraulic fracturing experiments can more accurately measure the fracture geometry due to smaller specimen size and improved monitoring capabilities. This paper presents laboratory work where hydraulic fracture treatments were performed using epoxy injection such that a propagating fracture could be stabilized and preserved at near-critical state. Constant backpressure was applied after hydraulic breakdown but before cessation of fracture extension to maintain near-critical state geometry. Preliminary results are presented giving measurement of fracture dimensions, including aperture, at the millimeter scale for a hydraulic fractured acrylic specimen. The pressure, flow rate, material strains, acoustic emissions, and video stills associated with this fracture are also presented and analyzed. A second experiment fracturing a 300×300×300 mm3 cubic foot granite block using epoxy is also discussed. Data regarding the interaction between shear and tensile dominated fractures is presented and discussed.
Number of Pages
Looking for more?
Some of the OnePetro partner societies have developed subject- specific wikis that may help.