The near-wellbore fracture geometry is important to hydraulic fracture execution and the subsequent post-treatment well performance. A fracture from an arbitrarily-oriented well"cuts" the wellbore at an angle and this limits the communication between the wellbore and reservoir. The stress concentration around the wellbore further complicates the near-wellbore fracture geometry. The fracture width at the wellbore can be much smaller than the maximum width, or it may even close when the fracturing pressure decreases below some critical value. The limited communication path may cause a "screenout" during fracture execution or large reduction in the subsequent production because of choked fracture efects. This paper first discusses fracturing conditions for an optimal communication path between the wellbore nd the reservoir. The near-wellbor fracture geometry is then determined. The effects of this fracture geometry on fracture execution and production are discussed. Critical fracturing pressures are also calculated for different wellbore orientations and in-situ principal stress magnitudes. Guidelines are provided to enhance the success of fracturing treatments.
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