Vast swamps developed at the time of the dinosaurs along the river systems which flowed from the western intermountain basins of British Columbia and Alberta, Canada.
The forests flora flourished under ideal growing conditions allowing the accumulation of plant material as peat. The conditions necessary for coal formation include a warm climate, high humidity, much rain, poor soil drainage and high acid soil levels. Over long periods of time and further deposition of sediments, eventually the mass of peat material is turned into coal.
Coal has many uses today, especially as a source of heat energy.