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The fractured aquifers fram the Serra Geral Formation play a major role in the Northeastem region of the State of Rio Grande do Sul since they are sources of hydric resources used for public supplying, industrial and agricultural activities. Such fractured aquifers are located in the volcanic sequence ofthe Serra Geral Formation and are subjected to structural systems. The main identified structures in the region correspond to type 2 lineaments characterized by fractures and fracture zones. These structures are due to the action oftwo orthogonal tension fields (east-west and north-south) which had effect on the whole region. As a result, extension structures were created (parallel and sub-parallel to the strain axes) which are usually filled up; and hybrid and shear structures (slanting structures between strain and traction axes) which may or may not present filling. Data integration showed that there is a strang correlation between lineaments and productive tubular wells, the northeastem structures (correlations with an outflow between 10 to 20 m 3n1 ) and the northwestem structures (relations with outflows above 20 m 3n1 ) being the main ones. The analysis of the orientations for each group of lineaments with productive tubular wells showed that for Northwestem structures the main direction is N30-60W, for Northeastem it is N20-30E, for North-South it is NOO-14E and for East-West it is N80-90W. ln relation to the unproductive tubular wells it was observed that the higher occurrence is associated to the Northeastem structures group, whose main orientations are N30-40E and N50-60E. The result ofthe structural characterization and its relation with fractured aquifers demonstrates the need for structural analysis (lineaments identification and field surveys) when prospecting fractured aquifers. Keywords: fractured aquifers, lineaments, Serra Geral FormationResumo Os aqüíferos fraturados da Formação Serra Geral têm grande importância na região nordeste o estado do Rio Grande do Sul, pois se constituem em fontes de recursos hídricos utilizados para o abastecimento público, desenvolvimento de atividades industriais e agropecuárias. Esses aqüíferos fraturados estão localizados na seqüência vulcânica da Formação Serra Geral, sendo condicionados pelo sistema estrutural. As principais estruturas identificadas na região correspondem a lineamentos do tipo 2 caracterizados por fraturas e zonas de fraturas. Essas estruturas resultaram da ação de dois campos tensionais (um leste-oeste e outra norte-sul) ortogonais que atuaram em toda a região. Como resultado foram geradas estruturas trativas (paralelas e sub-paralelas aos eixos de compressão) que em geral estão preenchidas e estruturas híbridas e de cisalhamento (oblíquas entre os eixos de compressão e tração) que podem ou não apresentar preenchimento. A integração de dados mostrou uma forte correlação entre lineamentos e poços tubulares produtivos, sendo que as estruturas nordeste (correlações com vazões entre 10 a 20 m 3n1 ) e noroeste (relações com vazões acima d...

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