A significant issue in the planned research and development (R&D) activities at Utah FORGE is the characterization of the in-situ stress. Previously, we reported constrained wellbore stress models for three vertical wells at FORGE: 58-32, 56-32, and 78B-32 (Ye et al., 2022). In this paper, we present the updated wellbore stress models for Utah FORGE, focusing on the deviated well: 16A(78)-32. To determine the maximum horizontal stress (SHmax), we integrated the drilling-induced fractures and the transverse fractures observed within the borehole image logs. We applied two methods: Method 1 directly solves the equation systems with SHmax as the only unknown parameter, while Method 2 uses a stress inversion technique to obtain the inversion results of three unknown parameters: the magnitudes of SHmax, the orientation of SHmax, and the fracture trace angle (ω). Method 2 appears to provide more reliable stress results, suggesting that the constrained SHmax ranges from 0.81-1.06 psi/ft indicating a normal to potentially transitional normal-strike-slip faulting regime. On the other hand, Method 1 provides scattered results, showing the magnitude of SHmax is about 0.90-1.21 psi/ft, suggesting the existence of possible strike-slip faulting in deep formations. Furthermore, the orientation of SHmax obtained from Method 2 ranges from N5E to N30E. This is consistent with the stress orientation indicated by drilling-induced fractures observed from the image logs. Our results also reveal the presence of thermally induced transverse fractures, though most transverse fractures could still be natural in origin.

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