The northern segment of the Araguaia belt, near the cities of Xambioá and São Geraldo do Araguaia, consists mainly of supracrustal rocks from the Estrondo Group, in addition to gneisses from the Colméia Complex, exposed in the cores of the Lontra and Xambioá structures, exposed in the cores of the structures from Lontra and Xambioá, and from rocks from the Pequizeiro Group, which make up a narrow strip at the western end of the area. Considering the geometry and nature of the larger structures as well as the complexity of the structural framework, the area was divided into 5 (five) sectors. According to this picture, it was deduced that the macro geometric arrangement corresponds to an imbricated system of ductile thrusts, with rare "nappe"-type features standing out. thrusts; holomorphic folds related to late thrusts, or the transpression between transcurrent systems; and transcurrent shear zones, interpreted as lateral ramps. At the mesoscopic level, the structures are represented by the mylonitic foliation, the stretch lineation, folds of different styles and the On the other hand, thin lamina analysis revealed microstructures such as: porphyroclasts and asymmetric porphyroblasts with pressure shadows; quartz ribbons; S-C arrangements, tectonic twins in feldspar crystals; pisciform features; quartz-feldspathic aggregates in the form of lenses, microbanding, and recovery features. chthonic, four main movements were characterized in the progression of shear deformation: the first is related to the intense imbrication of rocky bodies resulting from the propagation of ductile thrusts, which must have been accompanied by the individualization of the lateral slopes; the second is associated with the uplift of splinters from the basement, imposing kilometric folds in the initial arrangements, due to a second generation of thrusts that did not affect the uppermost packages. At this point, it is assumed that there was significant movement along the side ramps; the third refers to the rotation of the megafolds, preferably in the central part of the area, due to the intensification of movements on the side ramps; and the fourth corresponds to the imbrication that was superimposed on the geometric arrangement created by these lateral ramps. Tectonic evolution, as understood here, developed according to the oblique collision process of continental masses, with preferential transport of rock units from SE to NW. Finally, a brittle regime is recorded through fault and fracture systems that are associated with Paleozoic and Mesozoic extensional events and, in part, with the neotectonic framework.
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