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V cycle.
This cycle corresponds to the Phanerozoic epoch. In the whole it corresponds to the lower mental plane
(animal world). In comparison with the human life it corresponds to the period from 40 from 46 years.
As we already mentioned before, the last, Vth cycle went through a bit than a half of its development.
One can divide it into five periods 111,1(1)… million years each. Probably, after the end of the last ice
time a new, 6th period began, which corresponds to Holocene, begun only 11.500 years ago.
1. 555,5 (5)… – 444,4(4)… million years.
This period corresponds clearly enough to geological Caembrium (542-488.3 million years) and
Ordovician (488.3 – 443.7 billion years).
Main events of this period:
0.56 billion years – quantity of oxygene in the atmosphere reaches 1/3 from normal.
0.46 billion years – first terrestrian plants appear.
0.45-0.43 billion years – first dying out of organisms.
Материки концентрировались преимущественно вблизи экватора, что и способствовало
установлению теплого климата, вероятно, вместе с усилением эксплозивного вулканизма.
The main event of the Caembrium was emergence and rapid flourishing of the varied fauna of
invertebrates, which had a mineral skeleton, emergence and domination of trilobites. It appeared at the
background of the domination of warm climate and broad spreading of the epicontinental seas. To the
begin of the period megacontinent Gondwana was formed and future northern continents – Laurentia,
Baltia, Siberia, Sinokorea were separated with the oceans, which continued to expand in Caembrium: in
the present time their crust is represented with ophiolithes.
Main features of the Ordovician period:
-preservation of Gondwana unity and the square of other continents with contemporary maximal
expansion of intercontinental oceans (Japetus, Paleothetis, Paleoasiatic) in the middle of period; in the
late Ordovician the Takon orogenesis appears, which causes the essential changes in the inside structure
of some moving zones, especially of the Paleoasiatic ocean;
-domination of the warm climate in the course of early and middle Ordovician, then rapid cooling and
emergence of the cover freezing in Gondwana and its periphery in the connection with moving of
Gondwana into the polar region of South ocean;
-further development of organic world with possible emergence of terrestrian plants. Emergence of seaurchins. Graptolithes played an important part in the Ordovician. Molluscs and jawless fishlike
organisms were spreaded broadly in Ordovician.