BACIAS INTRACRATÔNICAS: GEOMETRIA NUMA SUPERFÍCIE ESFÉRICA E IMPLICAÇÕES NA ANÁLISE TECTÔNICA

Intracratonic basins: geometry in a spherical surface and implications for tectonic analysis ABSTRACT The intracratonic basins are the result of the flattening of the spherical surface of the earth or of the interior of the spherical plate. Their basements are nearly spherical surfaces too, convex outward. A model is developed to describe quantitatively this concept and to evaluate its tectonic meaning as a model applied to Parana basin (Brazil). The deformational evolution of the intracratonic basins has close relationship with the changes in the stress-strain crustal state introduced by vertical movements within the basin and horizontal the horizontal ones at the convergent plate boundaries. Keywords – intracratonic basins, tectonic evolution, crustal stress in basins, flattening the lithosphere.