Indirect boundary element analyses of hydraulic fracture interaction with the pre-existing natural fractures in a jointed hydrocarbon reservoir

Hydraulic fracturing is one of the most well-known methods in stimulation and enhanced recovery in oil and gas reservoirs. Determination of propagation path of hydraulic fractures (HFs) and created fracture network have a dominant role in increasing permeability of the reservoir. Reservoirs contain many natural fractures (NFs). Understanding the interaction behavior of the HF and NFs controls the fracture network created by the HF propagation. In this paper, a higher order displacement discontinuity method is uaed, the numerical model is verified by several analytical well-known problems in fracture mechanics. Three main behaviors may be named for the interaction of HF and NFs i.e. arrest, crossing, and opening. Two well-known interaction criteria are introduced. Then an algorithm is introduced to determine interaction of HF and NF. The algorithm and its implementation in a numerical model were tested against experimental results. Using higher order displacement discontinuity method the interaction of HF and NFs is investigated in various conditions. Results showed that the possibility of crossing for higher angle of intersection is higher. Also the HF energy reduces after each NF crossing. It means that HF has lower chance for crossing NFs after previous crosses.