| Summary: | Explanation of the evolution of the Earth's oceans, particularly the processes involved in the generation of the oceans, are important for understanding the general appearance of our planet, and for the solution of specific problems. A comparative study of the world's oceans shows there is a single genetic series in the evolution of oceans, and that the oceans of the world are at different stages in their evolution. The Arctic Ocean, dated as Cenozoic, is noted for its small size and shallow oceanic floor, extensive but passive continental margins, limited volcanism, significant crustal thickness, and a lack of Benioff zones. The Mesozoic, Indian and Atlantic oceans have much greater dimensions and depths than the Arctic Ocean, the crust is thinner beneath them, volcanism is much more extensive, and active margins, while in the initial phase of evolution, are limited in extent. The area of the most ancient (probably Paleozoic) Pacific Ocean is equal to the sum of the rest of the three oceans; it also has the greatest oceanic depth. Beneath the Pacific, the crust is thinned and is characterized by high permeability, because of which magmatism is particularly widespread. Active continental margins arc also extensive in the Pacific. The concept of evolutionary development of the oceans enables us to predict the comparative potential of oceans with regards to their oil and gas and ore content. RÉSUMÉ Les explications de l'évolution des océans de la terre, particulièrement les processus impliqués dans la formation des océans, sont importants pour compréndre l'aspect général de notre planète et pour la solution de problèmes spécifiques. Une étude comparative des océans du monde montre qu'il y a une suite génétique unique dans l'évolution des océans, et que les océans du monde en sont a différents stades dans leur évolution. ...
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