Vast deposits of coal originate in former wetlands—called coal forests—that covered much of the Earth's tropical land areas during the late Carboniferous (Pennsylvanian) and Permian times. However, many significant
Where did coal originally come from?
It is generally accepted that coal originated from plant debris including ferns, trees, bark, leaves, roots and seeds some of which accumulated and settled in swamps. This unconsolidated accumulation of plant remains is called peat. Peat is being formed today in marshes and bogs.
When and where was coal formed?
The conditions that would eventually create coal began to develop about 300 million years ago, during the Carboniferous period. During this time, the Earth was covered in wide, shallow seas and dense forests. The seas occasionally flooded the forested areas, trapping plants and algae at the bottom of a swampy wetland.