This map of the United States shows an inset area displaying highlighted areas of the smackover layer and sampling area. The Smackover Formation (highlighted in yellow) covers southern and eastern Texas, southern Arkansas, the upper half and eastern portions of Louisiana, the southern half of Mississippi, southwestern Alabama, and the Florida panhandle. covers part of. The sampling area is located in lower Arkansas (highlighted with a red stripe). (Source/Usage: Public Domain.)
RESTON, Va. — The United States may literally be sitting on buried treasure. Deep underground in southwestern Arkansas, scientists have discovered an unexpected blessing. That was enough lithium to power millions of batteries for electric cars. This discovery could free the United States from its dependence on foreign imports of this important mineral.
A groundbreaking study by the United States Geological Survey (USGS) revealed that the region has lithium reserves of between 5 million and 19 million tons. This is enough to meet the projected global demand for electric vehicle batteries in 2030 by more than nine times.
The discovery, published in Science Advances, comes at a critical juncture, with demand for lithium surging due to the global desire to build electric vehicles. The lightweight metal is essential for producing the rechargeable batteries that power everything from smartphones to electric cars, and until now the U.S. has had to rely heavily on imports for more than a quarter of its lithium supply. There wasn’t.
“Lithium is a critical mineral for the energy transition, and the potential for increased U.S. production to replace imports has implications for jobs, manufacturing and supply chain resiliency,” said USGS Director David Applegate. said in a media release.
Lithium is a lightweight metal that is essential for making rechargeable batteries that power everything from smartphones to electric cars. (Credit: Sashkin/Shutterstock)
What makes this discovery particularly interesting is where the lithium is located. It is dissolved in ancient seawater trapped within a geological formation called the Smackover, a vast limestone formation that spans several southern states. This underground reservoir was formed during the time of the dinosaurs in the Jurassic period and has long been known for its oil and bromine deposits. Now, another valuable secret has been revealed in that salt water.
To create this hidden treasure map, researchers used a sophisticated combination of old and new techniques. They collected water samples from the area and analyzed them at the USGS Salt Water Laboratory in Virginia. They then used artificial intelligence and machine learning to create detailed maps that predict lithium concentrations across the region, even in areas where they can’t sample directly.
“Our study provides the first estimate of the total amount of lithium present in the southwest Smackover River in Arkansas,” explains Katherine Knirim, the study’s principal investigator. “We estimate that there is enough dissolved lithium in the region to replace lithium imports, including from the United States.”
This map of the United States shows an inset area displaying highlighted areas of the smackover layer and sampling area. The Smackover Formation (highlighted in yellow) covers southern and eastern Texas, southern Arkansas, the upper half and eastern portions of Louisiana, the southern half of Mississippi, southwestern Alabama, and the Florida panhandle. covers part of. The sampling area is located in lower Arkansas. (Highlighted with a red stripe). (Source/Usage: Public Domain.)
Knirim cautions that these estimates only indicate how much lithium is present, not how much can actually be extracted.
“It is important to note that these estimates are field assessments; we do not estimate what is technically recoverable based on new methods of extracting lithium from brine. ”
One particularly encouraging aspect of this discovery is that much of this lithium-rich brine is already pumped to the surface as a byproduct of oil and gas operations. Instead of treating this brine as waste, it can be treated to extract valuable lithium, effectively turning a waste problem into a valuable resource.
This discovery could not have come at a better time. Demand for lithium, needed for electric vehicles and their batteries, is expected to soar as countries around the world push to reduce carbon emissions. The Arkansas deposit could help secure America’s place in the growing electric vehicle industry while reducing dependence on foreign suppliers.
Successful development of these lithium reserves could transform Southwest Arkansas into a major player in the green energy revolution, bringing new jobs and industry to the region and facilitating America’s transition to electric vehicles. There is.
Paper summary
methodology
To understand the potential for lithium extraction, the researchers used machine learning to analyze lithium levels in brine samples from the smackover layer. They collected data from both historical and recent samples, examining key factors such as depth, temperature, and other geochemical properties.
A machine learning model called “Random Forest” was trained to predict lithium concentrations across the region, creating a map that helped identify lithium-rich areas with potential for extraction. This approach helps avoid costly sampling by predicting areas where lithium concentrations are likely to be high.
Main results
The study estimates that the Smackover Formation brine in southern Arkansas contains between 5.1 million and 19 million tons of lithium. This represents the bulk of the US’s current lithium reserves, up to 136%. By creating maps, researchers identified zones in geological formations where lithium levels exceed those required for commercial extraction, marking these zones as areas with high potential for future lithium sourcing. I was able to.
Research limitations
This study had several important limitations. First, this study relies heavily on historical data, which may not fully represent current lithium levels. Also, while effective, machine learning models work best within a range of sample data and may not accurately predict extreme values (very high or very low lithium levels). Additional data from undersampled regions improves the accuracy of future models.
Discussion and key points
This study highlights the potential of the smackover layer as an important lithium source and suggests the potential to meet increasing lithium demand through battery production for renewable energy solutions. However, limitations in data quality and model reach suggest that additional sampling may help refine predictions and provide more accurate resource estimates. Successful extraction of lithium from these brines could reduce the United States’ dependence on overseas lithium resources.
Funding and disclosure
The study was funded by the U.S. Geological Survey, with additional support from state geological agencies. The researchers reported no financial interests that could influence their findings.
