Neoproterozoic-Cambrian structures as a guide to the evolution of the Bambuí karst in the Vieira river basin, Montes Claros, North of Minas Gerais, Brazil
Main Article Content
Abstract
The Brasiliano deformation imposed on the rocks of the Bambuí sedimentary basin, in the northern region of Minas Gerais, generated a system of folds, faults, and joints. These structures were studied on regional (1:100,000), semi-detail (1:50,000 and 1:25,000), and detail scales in the maps of caves (1:100). Based on these studies, it was concluded that in the region there is a cropping (epigenetic) karst in the limestones of the Lagoa do Jacaré Formation and another non-outcropping (hypogenic) in the limestones of Sete Lagoas Formation and that the main structures that controlled its development are the folds, joints (F1 and F2) and bedding (S0). The F1 joints have NNE-SSW direction, are parallel to the front thrust and to the folds’ axial planes, control the geometry of the surface drainage network, are the main directions of the rock faces of the limestone massifs, the karstic valleys, and the conducts of the studied caves. Whereas the F2 joints have WNW-ESE direction, are perpendicular to the F1 family, control the surface drainage network and the directions of the cave ducts. The intersection planes between the bedding and the joints and/or among different joints is what defines the geometry of the karstic features in the area. The F1 joints also coincide with the direction of the normal fault that controls the São Francisco river direction in this region. The faults, which are the deepest structures, can function as a connection among the different aquifers of the area, including the recharge of the non-outcropping karstic aquifers of the Sete Lagoas Formation.
Article Details
![Creative Commons License](http://i.creativecommons.org/l/by/4.0/88x31.png)
This work is licensed under a Creative Commons Attribution 4.0 International License.
The papers are published in the open access format, being freely available to any user, under a CC-BY Creative Commons license.
By submitting this manuscript for evaluation, the authors are aware of the CC-BY Creative Commons license. In the case of manuscript approval, the author responsible for the manuscript (corresponding author), hereinafter referred to as CEDENTE (ASSIGNOR), hereby assigns and transfers to CPRM-Serviço Geológico do Brasil, holder of the JGSB, free of charge, on his behalf and on behalf from all co-authors, the right of the first publication. This includes the rights of editing, publication, translation into another language and reproduction by any process, worldwide, today and in the future.
After the first publication by the JGSB, authors hold the copyright without restrictions and are allowed to disclose and distribute their work through personal website pages and institutional repositories.
At the same time, the ASSIGNOR declares that the content of the manuscript is of sole responsibility of the authors and that this content does not infringe the copyrights and/or other property rights of third parties, that is, that any contents of the manuscript and its attachments, if taken from other publications, are duly referenced and, when necessary, the permissions for publications of such contents were requested by the authors from the copyright holders; that the disclosure of images (if any) has been authorized and that it assumes full moral and/or patrimonial responsibility, due to its content, before third parties.