Complexity of near-wellbore hydraulic fracture morphology around perforated wells with various orientations in tight reservoir

Horizontal wells with multiple perforated fracturing is main method to improve well production in the tight formation. However, hydraulic fracture morphology remains obscure because of different horizontal stress contrast, wellbore direction, and pump rate, resulting in no guidance for perforation parameters design. To uncover the mask, a perforated wellbore fracturing model is established based on the continuous damage theory, combing with field data to investigate the effects of above three factors on hydraulic fracture morphology around wellbore. The results indicate that induced fractures could overlap and interact with each other when the wellbore is set along the direction of minimum horizontal stress. The induced fractures have narrow width because of stress shadow effecting. However, when angle between wellbore and the minimum horizontal stress direction increases, the induced fractures prefer to link up as a simple one. Moreover, induced fractures could propagate along and perpendicular to the wellbore direction under a small horizontal stress contrast, forming a complex hydraulic fracture morphology. A high pump rate resists stress shadow effecting and improves hydraulic fracture volume, but cannot decrease the complexity of near-wellbore fractures under a small horizontal stress contrast.