Experimental models of ‘Basement’ - controlled salients – application to the Proterozoic fold-thrust belt of the Quadrilátero Ferrífero (Minas Gerais, Southeastern Brazil).

Abstract
Scaled sandbox models are used to simulate the development of ´basement´-controlled, salients. We investigate the controlling factors on the development of closed curvatures in map-view, considering constant both the sand pack thickness and the space between obstacles. These models are compared with the Fundão-Cambotas Fault System in the Proterozoic fold-thrust belt in the Quadrilátero Ferrífero region, along the southeastern margin of the São Francisco craton. In the experiments, a pronounced curvature resulted from the margin-controlled salient process in the presence (i) of a basal ductile detachment, or (ii) of pre-existing structures. The results suggest that the convex-to-the-foreland, west-vergent Fundão-Cambotas Fault System that borders the Archean basement highs and displaced older Transamazonian structures westward, is partly a consequence of interaction of propagating thrusts with obstacles in the foreland
Description
Keywords
Experimental modelling, Salients, Brittle deformation, Ductile deformation
Citation
GOMES, C. J. S.; PEREIRA FILHO, M.; BRAGA, S. C. M. Experimental models of ‘Basement’ - controlled salients – application to the Proterozoic fold-thrust belt of the Quadrilátero Ferrífero (Minas Gerais, Southeastern Brazil). Anais da Academia Brasileira de Ciências, v. 75, n. 2, p. 249-263, 2003. Disponível em: <http://www.scielo.br/pdf/aabc/v75n2/v75n2a10.pdf>. Acesso em: 12 nov. 2015.