Horizontal well fracturing technology for reservoirs with low permeability

The horizontal well stress distribution and the rock failure criterion constitute a fracture initiation mathematical model, which was solved by the iteration method. Minimum horizontal principal stress and vertical principal stress have different influences on the fracture initiation pressure when the horizontal well orientation angle is different: the fracture is least likely to initiate when the angle is 0 and is easiest to initiate when the angle is 90°. The simulation result of 3-D hydraulic fractures propagation model matches well with the Fracpro-PT software, and it is suitable to simulate horizontal well fractures propagation. If the fracture interval is long, a multifracture propagation model could be built taking into account of the fractures interaction and the single fracture propagation model. Field horizontal well fracturing technology can be summarized as limited entry treatment and staged fracturing treatment, the limited entry treatment is simple with smaller reformation intensity; the staged fracturing treatment has higher reformation intensity but requires advanced facilities. The fracturing technology should be chosen according to the field situation.