CENTRAL ILLINOIS (WCIA) — A relatively new practice is allowing some farmers to capture carbon, leaving the door open for them to profit through carbon credits.

A small percentage of farms are using basalt — or crushed rock — in their soil. Crushed basalt in soil absorbs carbon dioxide indirectly, trapping the carbon.

Andrew Margenot, a professor of crop sciences at the University of Illinois, said it traps CO2 by speeding up a natural process called rock weathering.

“Weathering is a term that we use in geology to describe rocks decomposing. Rocks decompose, and by grinding up this rock, it happens 50,000 times faster than it would naturally,” Margenot said. “So this is also called accelerated or expedited rock weathering … The premise then to back up here is that by adding this crushed rock, we can speed up a process that consumes CO2 and thus takes it out of the atmosphere to mitigate climate change.”

He said the jury is still out on the process as a whole and in particular, whether the process produces more carbon dioxide as it eventually captures.