Almost all of the coal-forming
plants. The types of plants and coal-forming age by Diessel (1981) are as
follows:
-Algae, from Pre-Cambrian Times to
the Ordovician and single-celled. Very few coal deposit of this period.
-Silofita, from the Silurian Period
to the Middle Devon, is derived from algae. Few coal deposit of this
period.
-Pteridofita, age of Upper Devonian
to Upper Carboniferous. The main coal-forming material from Carbon
in Europe and North America.
Plants without flowers and seeds, spores multiply and grow in warm
climates.
-Gimnospermae, a period ranging from
Permian to Cretaceous Middle Ages. Heterosexual plants, seeds
encased in fruit, such as
pine, contain high levels of sap (resin) high. Type Pteridospermae like
gangamopteris and Glossopteris
is the main constituent Permian coal as in Australia, India and Africa.
-Angiosperms, from the Upper
Cretaceous period until now. Modern plants, the fruit covering the seeds, the
male and female in one flower,
less gummy than gimnospermae so that, in general, less well preserved.
Tidak ada komentar:
Posting Komentar