Arkansas might be home to around 19 million tons of lithium — researchers use machine learning to quantify lithium abundance in the Smackover Formation

Battery
(Image credit: Shutterstock)

Current known lithium reserves are under tremendous pressure due to soaring demand driven by the widespread use of lithium-ion batteries. A recent study by the USGS estimates that there may be approximately 5.1 to 19 million tons of lithium in Southern Arkansas, with the latter representing almost 136% of the United States' current lithium resource estimate.

Delving into the details, this lithium concentration is projected to be in the Smackover Formation brines of Arkansas. The Smackover Formation is a vast and permeable limestone aquifer—a formation of porous limestone rock that can carry water—dating back to the Jurassic geologic era. Importantly, this region is full of mineral-rich brine or salt water. As you may have guessed, these estimates refer not to lithium rocks but to lithium dissolved in brine.

The research team used fresh lithium concentration data in tandem with historical samples to train a machine-learning model that plotted a lithium concentration map, even in areas that didn't have lithium samples. A combination of this model and water testing led the group to the estimate that Arkansas may be housing up to 19 million tons of lithium. Extraction rates of lithium from brine are still a large variable, so the final output will be less than these initial figures; "We have not estimated what is technically recoverable based on newer methods to extract lithium from brines,” said Katherine Knierim, a Hydrologist.

lithium concentration in brines

(Image credit: USGS)

On a more industrial scale, the US relies on foreign countries for roughly 25% of its lithium imports. Researchers estimate that there is enough dissolved lithium in Arkansas to ensure the US no longer needs to depend on imports. In 2022, over 5000 tons of lithium was brought to the surface based on these calculations as a byproduct of the oil, gas, and Bromine industries.

If extraction of even five million tons (lower bound) is possible, this is over nine times what electric vehicles require by 2030. If, hypothetically, 100% of lithium was extracted, the amount of lithium obtained would be over 30 times the global demand in 2030.

Smackover Formation Map

(Image credit: Public Domain)

Work is currently underway on lithium extraction in this region. ExxonMobil, an energy company, acquired drilling rights in Arkansas in 2023. The company has set ambitious targets to begin extraction by 2027 and power a million electric vehicles by 2030.

The Smackover Formation is emerging as a strategically important location for the US. Otherwise overlooked byproducts of mineral extraction are now proving to be the future's goldmine: lithium.

Hassam Nasir
Contributing Writer

Hassam Nasir is a die-hard hardware enthusiast with years of experience as a tech editor and writer, focusing on detailed CPU comparisons and general hardware news. When he’s not working, you’ll find him bending tubes for his ever-evolving custom water-loop gaming rig or benchmarking the latest CPUs and GPUs just for fun.

  • Notton
    By the time whatever entity gets a Lithium mine, processor, and refinery up and running, I expect Sodium-Ion to have replaced Lithium-Ion batteries.
    Reply
  • Eximo
    Notton said:
    By the time whatever entity gets a Lithium mine, processor, and refinery up and running, I expect Sodium-Ion to have replaced Lithium-Ion batteries.
    Only for some applications, hopefully stationary ones.

    Don't expect power density miracles from any up and coming battery technologies. Always some lab breakthrough and or theoretical limit that doesn't end up making as huge an impact as they predict. The time it takes to bring costs down on new manufacturing processes also takes time while the Lithium NMC and LiFePO manufacturers have decades behind them. Not like research has stopped there either.

    Also the issue of scaling up a new battery technology. Sure cheaper to make a Sodium Ion today, but once there are MWhs of batteries being produced, there may be a new scarcity that increases production costs.

    Solid state batteries have shown some promise as a direct replacement for typical Lithium Ion. But major production is still some years off. I believe you can already get some laptop batteries though.
    Reply
  • Geef
    I know of a great way to generate power. No need for new battery storage. It is known as the Wheel of Pain and can be run in any weather day or night. It also makes huge dudes like Arnold. :p
    Reply
  • jg.millirem
    What kind of environmental horrors would this extraction unleash?
    Reply
  • Datahound6
    Glancing at the map, it seems likely that the Smackover formation extends into the Gulf of Mexico just offshore of the Florida panhandle. This may prove to be an ideal location for brine extraction -- few neighbors to NIMBY (20 miles offshore?) and the surplus brine can be simply dumped overboard from any processing facility.
    Reply
  • Dementoss
    Admin said:
    The Smackover Formation is a vast and permeable limestone aquifer—a formation of porous limestone rock that can carry water
    Limestone is water soluble, it is always full of cracks, holes, caves and underground rivers. I grew-up on The Mendip Hills in the West of England. They are limestone and, riddled with holes...
    Reply
  • BFG-9000
    Eximo said:
    Only for some applications, hopefully stationary ones.

    Don't expect power density miracles
    Incredibly, you can already buy Sodium-Ion for very reasonable prices from Dongguan GoKWh. Sure, power density is a bit lower than LiFePO4 but look at those $50 motorcycle batteries which can be direct replacements for lead-acid in many climates.

    This is only possible because you can charge Sodium-Ion down to -10°C/14°F. EVs using lithium chemistry have to run a heater until the cells are all above 0°C/32°F before they will begin charging, greatly extending charge times in subzero weather. And there are of course many stationary applications where the heater requirement would waste many of the limited hours of solar you can get in the winter. With demand for batteries projected to rise rapidly, any alternative allows lithium to be reserved for more high-performance uses.
    jg.millirem said:
    What kind of environmental horrors would this extraction unleash?
    As with oil, the most easily extracted forms are obviously collected first before you resort to more difficult ones like shale oil or this brine. And fracking is commonly used to extract brine from deep rock so expect the usual earthquakes and aquifer contamination.
    Reply