Geologia estrutural e geotecnia do maciço granítico do Alto da Cabeça Santa (NW de Portugal) : implicações para a gestão do georrecurso da pedreira da Mimosa : implications for the georesources management of Mimosa quarry

Abstract

This work presents the results of the structural geology, geomorphology and geotechnics studies of block delimitation of a granitic rock mass. For this characterisation, the scanline sampling technique of discontinuities has been applied to the study of free rock mass faces from Mimosa granitic quarry (Alto da Cabeça Santa, Penafiel; NW Portugal). For that purpose, the surrounding area of the open quarry as well as selected granitic outcrops were studied using the following tools: surface geological/geomorphological mapping, structural geology and geotechnics/geomechanics techniques. So, a morphotectonic analysis of topographic map and geological survey has then been carried out. In addition, the evaluation methods of field data for discontinuities sets and the statistical characterisation of their orientation, spacing and extension are also presented. The results achieved at different scales are compared in order to detect the presence of a multiscale fracture network pattern. The use of these techniques for understanding the rock mass block delimitation may contribute to improve the sustainable management of the georesources from Mimosa granitic quarry.