Numerical Modeling of Stimulation and Circulation in Utah FORGE Wells

Abstract

In this paper we simulate fluid circulation between the Well16A(78)-32 and the Well16B(78)-32 in the Utah FORGE. The coupled fracture/reservoir numerical approach is first verified with the analytical solutions, and calibrated using a lab-scale EGS experiment with hydraulic fracturing, fluid circulation, and thermal transport to clarify the physical properties controlling fluid flow and energy transport in stimulated rock. Then we estimate fluid flow from the injection well into the fracture network resulting from the stimulation of the Well16(A)78-32. We study injection-induced permeability increase and the pressure and temperature change around the stimulation zone. The influence of fracture geometry and stimulated permeability change on fluid flow in response to step-rate injection schedule is also presented. In addition, we investigate the observed pressure data from the injection and production well in FORGE circulation test and calibrate the model to estimate the stimulated reservoir permeability. The study helps characterization of the stimulation outcome and the rock mass transport properties at the Utah FORGE.