In April 2022, three hydraulic stimulation stages were completed near the toe of injection well 16A(78)-32. In April-June 2023 the production well, 16B(78)-32, was drilled ~300 ft above and roughly parallel to the highly-deviated injection well. Three intervals in the production well cored through stimulated crystalline reservoir rock, totaling 135.8 ft. Core from stimulation 1 (10,430 to 10,493 ft) and 3 (9,800 to 9,853 ft) consists of dark-colored, banded gneiss. Core from stimulation 2 (10,250 to 10,304 ft) consists of light-colored granitoid. Fractures in the core were assigned the following classifications: 1) planar; 2) semi-planar; 3) unbroken mineralized; 3) rough; 4) concave-convex; and 5) curviplanar. Within individual core runs coherent fracture measurements of planar features (planar, semi-planar and unbroken mineralized fractures) were obtained. Measured fracture orientations were rotated to match the trajectory of the deviated well. A depth correction and an axial rotation was then applied to best fit microresistivity image logs. Planar features dominantly strike NNW-SSE in alignment with the maximum horizontal stress. Planar features were most common in gneiss from the stimulation 1 and 3 cores, with the stimulation 3 core containing most planar features. The stimulation 3 core may have been adjacent to a reactivated natural fracture zone. Fractures containing secondary vein minerals were open and filled with fluid in the reservoir prior to the drilling of 16B(78)-32. The majority of the planar features are mineralized, with calcite being the most common phase. Calcite ± anhydrite may have precipitated from the injected fluids at reservoir temperatures. Cross-cutting relationships suggest closely spaced, curviplanar fractures in the bottom of the stimulation 1 core are impermeable features in the reservoir.

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