Analysis of the external geodynamics of the river damaged by the fundão dam break, Mariana – MG: between Bento Rodrigues and Barra Longa

Abstract

The present work evaluates the external geodynamics of the Rio Gualaxo do Norte, from Bento Rodrigues to Barra Longa, after the rupture of the Fundão dam in Mariana. The watershed of the Doce River was contaminated and consequently the physico-chemical parameters of the basin were altered, causing in the change of color, turbidity, among others, negatively impacting several water courses. Due to the muddy sea containing the mining tailings, the natural course of the stretch of river under study was modified, as well as the biota, including vegetation near the rivers, also known as gallery forest. The damages caused were diverse, leading to changes in the surface of the river where the tailings wave passed. In this way, using multitemporal images obtained by Google Earth and the geographic information system ArcGis, it was possible to analyze and identify the transformations that occurred through maps that demonstrate areas where the changes in the river bed in terms of displacement and dimensions were clear, which directly affects the entire local ecosystem.