Condicionamento Estrutural Sobre O Aqüífero Barreiras E Sistema Lacustre Do Bonfim-Nísia Floresta-Rn

A cenozoic sedimentar region, localized near the eastern coastline of Rio Grande do Norte state, Brazil, was studied. This region contains the Bonfim lake that is an importante source of potable water to supply the cities in the region, including Natal (capital of the state). A joint study of morphotectonic, geologic, gravimetric and resistivity data revealed that the shallow structural trends are aproximately paralel to the deep structural trends. Based on this concordance, it is suggested that the shallow structures were formed, at least in part, activating the older and deeper structures. The Bonfim lake is localized on the crossing of two regional trends; these structures define a graben, which is resposible for the local increase in the saturated thickness of the Barreiras aquifer. The refered graben conditionates the groundwater flow from the Barreiras aquifer to the Bonfim lake.