Multi-stage hydraulic fracture monitoring at the lab scale

We introduce a novel experimental and modeling approach to perform lab-scale multistage hydraulic fracturing in Poly-Methyl-Meth-Acrylate (PMMA) and study pressure-based methods to monitor hydraulic fracturing. The approach combines an internal circular V-notch method for fracture initiation with a method for creating hydraulic isolation between subsequent stages. Using high-resolution models of fracturing experiments with injection and monitoring wells, we present novel results of displacement, pressure, and stress evolution around the wells. We identify injection-induced rotational deformation in the domain and asymmetric growth of the hydraulic fracture. We quantify the role of the monitoring well on the rotational deformation and the fracture asymmetry. We analyze the role of undrained deformation in generating the monitor well's pressure response to individual fracture stages at the injection well. Our results show that lab-scale multistage hydraulic fracturing can be a useful tool to estimate the geometry and property of a hydraulic fracture using pressure data from offset wells in the field.