Question

What happens to carbon that has been in the soil for millions of years​

Answer 1

The element carbon is a part of seawater, the atmosphere, rocks such as limestone and coal, soils, as well as all living things. ... When plants and animals die, their bodies, wood and leaves decays bringing the carbon into the ground. Some is buried and will become fossil fuels in millions and millions of years.

Step-by-step explanation:

Answer 2

Heat and pressure compress the mud and carbon over millions of years, forming sedimentary rock such as shale.