Caracterização estrutural de um segmento da rampa lateral de Capitólio, limite norte da nappe de Passos (MG)

Abstract

Structural mapping of a Capitólio lateral ramp section, northern edge of Passos nappe - Minas Gerais state, Brazil. The northern edge of Passos nappe, southwest of Minas Gerais state, is marked by a lateral ramp system called Capitólio Lateral Ramp. This ramp is the contact of the Internal and External domains of the Southern segment of the Brasilia Fold Belt. A detailed study of these domains permits to consider a model for the evolution of this ramp, explained as the vertical structures, which marks External Domain, changing to sub-horizontal structures verified in Internal Domain, both striking NW-SE. The contact between these domains is distinguished by a later thrust (D3) which obliterates the initial registers of the development of the lateral ramp, a steep plane (D2). The covered portion of this history involved complex deformation models, where by rotation of the vorticity axis is possible to see a transition of a vertical to horizontal Y-Monoclinic Shear Zone, respectively in the ramp and flat of the nappe.