Being burried under soil and mud changes peat into coal through extreme heat and pressure in a swamp over a long period of time.
Fens form non-acidic peat.
Being burried under soil and mud changes how fens form.
being burried under soil and mud changes how what forms?
Options:
* cacti
* deltas
* fens
* potash
* bamboo
* rivers
* roots
* mildew