Weak formation bedding planes create a unique mechanism for hydraulic fracture height containment. They arrest the vertical growth of hydraulic fracture.The propagation across them may or may not occur. To quantify this fracture behavior,first we developed an analytical model of the elastic T-shaped fracture contact with frictional and cohesional interfaces.The model evaluates the fracture blunting and the shear activation of the interfaces.It predicts the buildup of the net pressure necessary for the fracture to cross the given interface.Next we conduct numerical simulations of the 3D fracture propagation in a formation with closely spaced horizontal interfaces.These simulations manifest intermittent and decelerated fracture growth in height,especially with low-viscosity fracturing fluids.This mechanism of fracture height containment is independent of the multilayer stress-contrast mechanism used conventionally.Combined with the stress mechanism,the fracture height containment model could alleviate the problem of height growth overestimation in some fracturing simulation cases.
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