pressure and heat
The first fossil records of vascular plants that is land plants with vascular tissues Fossil ferns and seed ferns include Pecopteris Cyclopteris
Ancient plants.
p
Ferns and their fossil remains have been found on every continent
Because fern is a popular plant now and in the dinosaur days
The ferns have been compressed into 'coal' and we use coal as a source of energy - hence 'fossil fuels'.
The fossils were of Glossopteris (extinct seed ferns).
Ferns appeared in fossil records about 360 million years ago.
Usually volcanic eruptions and age.
Canada once had a much warmer climate.
It is coal
They are the cause of the formation of fossil fuels