Stanford Geothermal WorkshopFebruary 9-11, 2026

The Smackover Formation in the southern United States has recently emerged as a promising reservoir for lithium (Li) hosted in subsurface brines, with opportunities for co-production alongside geothermal energy. This study develops a stochastic assessment of lithium and geothermal resource potential in the northern Smackover using publicly available brine chemistry datasets that span both lateral and vertical sampling depths. Variogram analyses quantify spatial continuity, revealing long horizontal correlation ranges (10-40 km) but much shorter vertical ranges (250-1,000 m), which guided an anisotropic inverse distance weighting interpolation of Li concentration. The resulting 3D model delineates subsurface enrichment zones and yields an estimated seven million tonnes of total Li in-place across ~770 km3 of reservoir volume. Incorporating stochastic distributions of porosity, oil–water contact, and extraction efficiency indicates that only ~0.3 million tonnes are realistically recoverable, with recoverability limited primarily by low effective porosity and non-uniform brine saturation. Geothermal potential was evaluated using an analytical enhanced geothermal systems framework that assumes parallel fracture flow and constant heat extraction over a 30-year plant lifetime. Temperature drawdown estimates between 2,300 and 2,600 m depth (12-21°C) were combined with stochastic sampling of seven thermophysical and operational parameters to compute power density. Thermodynamic maxima range from ~8 to 14 W m-2, whereas realistic power densities cluster narrowly between 0.48 and 0.86 W m-2 due to low conversion efficiencies and modest geologic success factors. Together, these results highlight substantial Li endowment but modest geothermal potential and demonstrate the utility of stochastic co-resource assessment for informing future development strategies in the Smackover Formation.

Topic: General