3D Time-Lapse Magnetotelluric Modeling and Inversion of Hydraulic Fracturing: Synthetic Model Studies

Summary This study analyzes the time-lapse responses in the reservoir stimulation volume (SRV) before and after hydraulic fracturing through three-dimensional magnetotelluric (MT) numerical simulations and inversions. The pre- and post-fracturing states of an enhanced geothermal model are used to analyze the sensitivity of time-lapse monitoring. For the forward modeling, the three-dimensional finite element method is used to simulate the time-lapse response before and after fracturing, and the results are well analyzed. While the L-BFGS optimization algorithm is employed to perform separate inversions for different stages, and the differences in the inverted models are analyzed as the results of time-lapse inversion. This results demonstrate that time-lapse forward response can better qualitatively analyze the spatial distribution of SRV. At the same time, the time-lapse inversion results we defined can track the boundaries of SRV more effectively compared to separate inversions.