marți, 1 aprilie 2008

OBSERVATIONS ON THE CAUSES THAT LED TO THE CARPATHIANS OROGEN'S TORSION

The present paper does not deal with the structure of the Carpathian Mountains, which is sufficiently known from a large number od studies, among which we mention some syntheses: Murgoci 1910, Codarcea 1940, Mutihac, Ionesi 1974, Sandulescu 1984, Mutihac 1990 etc.

We shall only mention the fact that the Carpathian orogen includes deposits that underwent metamorphism and which are of ante-Cambrian and Early Palaeozoic age, as well as continental deposits that have not been affected by metamorphism and which date from the Carboniferous and Permian periods. These continental deposits - the Carboniferous ones, with coal and the Permian ones, with clay and red sandstone - belong to the Laurentia continent, which also comprised the Baltic Shield (Tătărâm, 1988). Back then, this land mass was situated between the Equator and the Tropic of Cancer (Petrescu, 1990) and it took part, at the end of the Permian Period, at the creation of the Hercynian orogen, which joined Gondwana with the northern continental masses, forming thus the supercontinent of Pangea.

During the Early Triassic. it began the opening of the Atlantic Ocean, the northen continental masses, separated in Laurentia and Eurasia, being pushed towards northeast and northwest.

Obductions also occured from place to place. In Triassic within the unstable Tethyan domain, the first important foldings took place


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