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All plants were responsible for the transformation, but Archaeopteris was important because it made up 90 percent of the forests during the last 15 million years when these changes accelerated" ..."It was the first plant to produce an extensive root system, so had a profound impact on soil chemistry".
2,500,000,000 to 542,000,000 years ago The Proterozoic Eon: the most recent part of the Precambrian Supereon.
The end-Frasnian extinction was most pronounced in tropical environments, particularly in the reefs of the shallow seas.
Reef building sponges called stromatoporoids and corals suffered losses and stromatoporoids finally disappeared in the third extinction near the end of the Devonian.
It mentions the following periods to indicate how long ago coal was formed: Carboniferous followed by 359,200,000 - 326,400,000 years ago Dinantian series or epoch from the Lower Carboniferous system in Europe 326,400,000 to 313,400,000 years ago Namurian stage in the regional stratigraphy of northwest Europe are found - Silicious Grit, providing stone for building and millstones - Shale - then lime-stone and toadstone alternately.
The veins of metallic ores appeared in the limestone.
writes of fine-grained greenish sandstones deposited in freshwater in which land plant fossils are well preserved.
"Among the most attractive of these" tree-fern once called Cyelopteris (Round-leaved Fern), re named Palasopteris Hibernicus (Primitive Irish Fern). It was the "monarch of the primeval forests" whose "graceful fronds bent over the clear waters of a lake".
This was not adopted, but his division into Mississippian, for the 's "Story of a piece of coal" focuses on coal formation, but includes a section on the carboniferous limestone.
It lists (but does not discuss) the intervening millstone grit.
He began to do this in 1866 in the General Morphology. about 419,2000,000 to 393,300,000 years ago Early Devonian The vegetation of the early Devonian consisted primarily of small plants, the tallest being only a meter tall.
By the end of the Devonian, "The earth's atmosphere was changing rapidly, going from perhaps 10 percent to 1 percent CO2 and from about 5 percent to 20 percent oxygen over a 50- million year period in the (late) Devonian period.
By carboniferous [carbon bearing] soils, Richard Kirwan in 1799 meant the "various sorts of earth or stone among or under which coal is usually found".