The Menengai Caldera is in a complex structural zone within the Kenyan Central Rift and hosts the Menengai Geothermal Field. In assessing the subsurface characteristics of many geological resources, knowledge of in-situ stress orientations and magnitudes at depth is essential. Acoustic televiewer logging campaigns carried out in Menengai Geothermal Field between 2018 and 2019 in the production zones of three geothermal wells, have provided an on-site assessment of horizontal in-situ stress orientation in an area lacking such data. Data generated from drilling-induced features in the Menengai Geothermal Field revealed that the average SHmax orientation for MW-34 is NW-SE, whereas the average SHmax orientation for MW-20B is NE-SW, and the average SHmax orientation for MW-15A is NNE-SSW. Subsurface variations of in-situ stress orientations are related to large-scale features such as fractures, fissures, and fault architecture in the geothermal field. The NW-SE SHmax in-situ stress orientation around MW-34 agrees with the Molo (TVA) structural orientation, the Menengai pre-caldera shield orientation, and the Aswa shear zone. The NNE-SSW strike direction of the southern Kenyan Rift Valley, which changes orientation at the triple junction, is compatible with the NE-SW and NNE-SSW SHmax orientations of MW-20B and MW-15A. MW-34 is aligned to the Solai TVA/Graben because of its NE-SW Shmin orientation. In addition, the MW-15A's almost E-W Shmin orientations coincide with the Kenyan Rift's extension direction, which corresponds to the orientation of the E-W striking horsetail fracture inside the Menengai caldera. Localized stress perturbations manifest as rotations of BOs or DITFs orientations along the well as a function of depth.
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