Assessing Fracturing in Weathered Granites: The Example of the Mondim de Basto Granite (Northern Portugal)

Abstract

Fracturing is the most limiting factor in the extraction of large blocks of granite for gang saw processing and should be carefully studied in the exploration stage. This paper presents the results of the fracturing evaluation of the granite from the quarries of Mondim de Basto, located in the north of Portugal. This very weathered granite has a high market demand and its commercial value is controlled by its yellowish brown colour. The fracturing was evaluated based on the mean/median joint spacing, as well as the volumetric joint count. The results stress the difficulty in obtaining large blocks since few places have the appropriate degree of jointing.