Dzieło Alfreda Wegenera a teoria ekspansji Ziemi

Abstract

The work of Alfred Wegener against the theory of expanding Earth.A b s t r a c t. Wegener‘s Pangea comprised all the continents during Permian times, surrounded by the Panthalassa all-ocean, much wider than the recent Pacific. The process of widening of new oceans (Atlantic, Arctic and Indian) during the Pangea breakup should be simultaneous with the shrinking of the pra-Pacific. However, there is much evidence that there are close biogeographic links between continents surrounding the Pacific, and the perimeter of the ocean becomes larger. If the Pacific expands like the other oceans, the Earth expansion is inevitable. The plate-tectonic fundamentals of supercontinent reconstructions refer to the hypothesis of the cyclic evolution of continental plates and to the assumption that plate collisions result in amalgamation of successive supercontinents followed by their break-up. As the result, the term “supercontinental cycle” was introduced. Thus, the Pangea history becomes a sequence of different consecutive Pangeas. Two periods of Precambrian supercontinent amalgamation were distinguishedbased on the supercontinent cyclicity hypothesis, leading to the formation of Meso-Neoproterozoic Rodinia and the Early Proterozoic Pre-Rodinia supercontinent. Pre-Rodinia, Rodinia and Pangea were strikingly similar to one another. To explain this phenomenon, a process of self-organization of tectonic plates is invoked. On an expanding Earth, there was only one supercontinent – Pangea – composed of continental lithosphere surrounding the planet smaller than the present Earth. The break-up process of the supercontinent occurred only once during Earth‘s history. Earth expansion offers a reasonable solution to the main plate-tectonic paradox that the continents could have been repeatedly separated and returned to the same unique configuration.