NUMERICAL SIMULATION OF HYDRAULIC AND NATURAL FRACTURE INTERACTION AND PROPAGATION

Julio Alberto Rueda Cordero¹; Cristian Mejia Sanchez.²; Deane Roehl¹

¹ Puc Rio de Janeiro; ² Tecgraf Puc-Rio de Janeiro

doi:10.20906/CPS/CILAMCE2017-0330

Resumo

Production of unconventional reservoirs has revolutionized strongly the oil and gas industry through the development of innovative applications such as horizontal drilling, microseismic monitoring and shale stimulation by hydraulic fracturing. However, pre-existing fractures in hydrocarbon reservoirs complicate hydraulic fracture propagation and eventually the microseismic interpretation of the stimulation. In addition, the interaction of hydraulic fractures and natural fractures may lead to complex networks of fractures, which can connect with shallower aquifers or geological faults increasing the risk of fault activation. This work presents a numerical technique using the finite element method to study the interaction between hydraulic fractures and natural fractures in order to predict the direction of fracture propagation. The fractures were simulated using a coupled hydro-mechanical interface element with damage and Mohr-Coulomb constitutive models to represent the hydraulic and natural fracture behaviors, respectively. Several scenarios were simulated for hydraulic fracture regarding the intersection with natural fracture. The comparison between the numerical results and the published experimental results by Blanton (1982) shows good agreement. The three main possibilities of interaction events, opening, crossing and arrest, are predicted. Finally, the results show that the most important parameters which affect the interaction between natural and hydraulic fracture are the in-situ stresses and the orientation of the intersection.

Palavras-chave: Computational geomechanics; fault reactivation; hydraulic fracturing; fracture propagation, ; Interaction FH and FN