Caracterização de descontinuidades com o auxílio de Vant aplicada à pesquisa de rocha ornamental no Complexo Metamórfico Palma, São Gabriel (RS)

Abstract

Currently, ornamental stones have gained prominence across the markets, national and international, because of the added aesthetic value to them. In order to achieve good levels of productivity and quality, important analyzes, related to extraction and processing, must be carried out, within which structural analysis stands out. This is an important tool for the analysis of massive rock. With the development and support of new techniques for the acquisition of the structural data, such as the aero photography from UAV (unmanned aerial vehicle), and it was possible to generate satisfactory results in less time. The study area located in the southern region of São Gabriel - RS in the metamorphic complex Palma pelitic - calcium silicates unit has been identified as ripe for research focused extraction of quartzite natural stone. This project mapped, described, and quantified 302 discontinuities, these 176 in target area 1 and 126 in the target area 2. The analysis of the data was performed by means of the aid of the stereographic projections and aero photography, with the use of the technique of areal sampling. At last, we observed that the main problem is the intersection of the low-angle fracture systems with NE-SW and NW-SE (more frequent in the quarry), that cause a high degree of weathering caused by the increased percolation of fluids. With this, they determined the areas with the least number of intersections of these discontinuities, interpreted as more favorable to the extraction of ornamental rock in the area.