油井或可成为关键矿产的矿井

Engineered fluids could extract metals from low-grade ore in vast underground reservoirs tapped by fracking PAUL VOOSEN The mine of the future may look a lot like the oil well of the past. Researchers are exploring whether the vast network of oil and gas wells drilled across the United States can be repurposed to extract critical minerals from the rock formations below—elements the U.S. needs for solar cells and electric vehicles and, for now, has to import from China and other countries. The idea builds on fracking: pumping huge volumes of fluid into underground rock layers to fracture them and bring oil, gas, and wastewater back to the surface. …