Fracture and lineament data used together to indicate fractured aquifer zoning factors

Abstract

Lineament tracing has been used to infer structural trends, and it is a preliminary step in studies of fractured aquifers. In order to evaluate the use of this tool for zoning fractured aquifers, the following methods were adopted: survey and analysis of fractures; elaboration of lineament maps at various scales; and elaboration of lineament rose diagrams for lithological and geomorphological units. The results indicate that: the systematic survey of fractures is essential to confirm the correlation between lineament and fracture trends; fracture data must be collected on the various lithological types of a region, as some fracture sets may be exclusive or more frequent in certain lithological units; lineaments must be interpreted at various scales, including those that are suitable for the purpose of the study; the lineament total length rose diagrams are more suitable for identifying the intensities of the several structural trends; lithological and morphological maps (eg relief forms, ICR and drainage patterns) should be tested to delimit structural domains (zoning) in fractured aquifers. It was concluded that, with the identification of fracture trends and linea-ments, as well as the identification of factors that have the potential to delimit regions with distinct fracture configu-rations, a first and fundamental step was taken towards the delimitation of structural domains in fractured aqui fers. This delimitation is fundamental for numerous applications, including the elaboration of hydrogeological models and minimization of risks in engineering works.