The creation of a hydraulic fracture changes the stress distribution in the vicinity of the fracture. This stress shadow can influence the growth of subsequent fractures. Immediately after a hydraulic fracture treatment is pumped, the width of the propped fracture and the associated induced unpropped (IU) fracture network is at its maximum. The hydraulic fracture and the induced unpropped fractures close as a result of fluid leak-off over time. This implies that the stress shadow in their vicinity also decreases over time. Complete closure of induced, unpropped fractures can significantly reduce the stress shadow and make subsequent fracture stages less susceptible to fracture interference and more efficient by avoiding wastage of fluid / proppant into preexisiting fractures. This suggests that increasing the time between successive fractures in a wellbore will lead to improved fracture performance.

Using geomechanical computations we show that waiting for longer times between successive stages of a horizontal well allows for a reduction in the stress shadow and less fracture interference leading to a more efficient fracture network by successive fractures in a horizontal well. We, therefore, propose the idea of establishing a minimum time between successive fracture stages in a well. The time required for the induced un-propped fractures to close can be calculated from our models and varies based on the reservoir and fluid properties but is of the order of hours.

This controlled time-delay in fracturing can be achieved in several ways, without wasting valuable rig time in the field. We suggest several alternate innovative strategies to achieve this on the field. For example, two-well or multi-well zipper fracs can be pumped, hence increasing the time between fractures in a given well substantially (by several hours). Alternatively, in the Texas Two Step method it would be better to pump the fractures in the sequence 1, 3, 5, 2, 4 than the sequence 1, 3, 2, 5, 4 where the numbers represent the sequence of the fractures along a well starting at the toe. We propose several other fracturing sequences for multi-well pad fracturing applications and suggest how the impact of a multi-stage, multi-well pad fracturing treatment can be enhanced while conserving the time and resources used.