This paper focusses on the type of hydrogeological testing and sampling methods applied at two UK geothermal lithium exploration sites, to define their extent and extraction potential. The results highlight the value of combining different hydrogeological, geophysical, and geochemical techniques to further the interpretation of geothermal structures. Hydraulic testing and samples from packer isolated intervals provided higher precision and higher confidence data that form the basis needed for exploration. Combing geophysical methods such as pumped impellor, Electrical Conductivity (EC), temperature, and Acoustic Televiewer (ATV) logging, provided higher resolution data, which has proved useful for the identification of controlling structures and refinement of conceptual models.
