LITHIUM SOURCES OF OILFIELD WATERS IN TEXAS AND NEIGHBORING STATES

There has been a reliance on imported lithium in the U.S. to support the energy transition and a need to develop domestic Li sources for national security. A recent preliminary study exploring the potential for Li production from oil field waters in the U.S. Gulf Coast region, including lithium concentration data collected from ~2450 formation water samples, shows significant potential for lithium resources from this feedstock in states along the greater Gulf Coast (NM, TX, OK, LA, AR, and MS).

Aqueous Li distribution is log-normal, typical of trace elements, with background levels in the 0-20 ppm range. Elevated concentrations (≥80 ppm) are relatively restricted to the following formations:

• Jurassic Smackover Formation, (several samples ≥100 ppm Li);
• Permian and Pennsylvanian Granite Wash in the Anadarko Basin of Texas (average 118 ppm Li); and
• Cretaceous Edwards Formation of South Texas (several samples ≥100 ppm Li).

Genetic links for Li enrichment and evolution are lacking, but high Li seems to increase with depth and with total dissolved solids. New data using lithium isotopes shows a range of potential sources across Texas basins. Smackover Formation brines show a δLi⁷ (‰) range of 7.95–12.58, similar to the Eagle Ford trend 7.75–12.26, but very different from the Anadarko Basin 19.33–34.99, and the Permian Basin -5.05–16.04, discriminating between seawater or saline groundwater, continental geothermal fluid and upper continental crust derived origin for lithium resources.