The hard rock aquifer in semiarid: analysis of models based on geological-structural data and airborne and terrestrial geophysical methods

In a large area of NE Brazil, where the effects of the semi-arid climate and crystalline terrain overlap, hard rock aquifers are the only sources of water, especially in periods of prolonged drought. The traditional location of wells, based on geological-structural, geomorphological and remote senso...

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Detalles Bibliográficos
Autores: Nascimento da Silva, Carlos César, Medeiros, Walter Eugênio de, Jardim de Sá, Emanuel Ferraz, Lima, Maria da Guia
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2023
País:Brasil
Institución:Associação Brasileira de Águas Subterrâneas
Repositorio:Águas Subterrâneas (São Paulo. Online)
Idioma:portugués
OAI Identifier:oai:ojs.aguassubterraneas.abas.org:article/30197
Acceso en línea:https://aguassubterraneas.abas.org/asubterraneas/article/view/30197
Access Level:acceso abierto
Palabra clave:Groundwater
Hard rock aquifer
Structural geology
Airborne and terrestrial geophysics
Semiarid.
Água subterrânea
Meio fissural
Geologia estrutural
Geofísicas aeroportada e terrestre
Semiárido
Descripción
Sumario:In a large area of NE Brazil, where the effects of the semi-arid climate and crystalline terrain overlap, hard rock aquifers are the only sources of water, especially in periods of prolonged drought. The traditional location of wells, based on geological-structural, geomorphological and remote sensor product analyses, involves high exploratory risk, resulting in about 30 to 40% of failure. This stems from the difficulty of assessing which are the dominant discontinuities (fracture or foliation), as well as which have higher hydrogeological potential. In this research, data from airborne (electromagnetic and magnetic) and terrestrial (geoelectric) geophysical surveys were integrated, in addition to structural analysis with a neotectonic bias. With the aim of improving the work of well locating, the results obtained demonstrate that the riacho-fenda and eluvial-alluvial trough models commonly coexist, allowing to outline their spatial distributions. In addition, it was possible to identify important geological and geophysical aspects to discriminate in the field which model effectively occurs.