The Southwest Água Azul do Norte and south of Ourilândia do Norte, southeast of Pará, is a swarm of mafic dykes of the felsic composition, with dominant NW-SE direction, embedded in rocks trondhjemíticas, tonalíticas, granodiorite, leucogranite-potassic Archean greenstone belts and Granite-Greenstone Terrain of Rio Maria (TGGRM) southeast portion of the Central Amazonian Province, eastern edge of the Amazon Craton. Dykes studied Ourilândia do Norte–Água Azul do Norte bodies include tabular, subvertical, oriented in NW-SE direction with a length around 500 m thickness of approximately 20 m. They are located in an area where peneplanizada emerge in the form of discontinuous ridges and rolled blocks, some of these dykes occur embedded in rocks trondhjemíticas Archean and Paleoproterozoic granites also the Seringa and São João were identified petrographically, three major groups of dikes: diabases texture intergranular and subofítica; andesite with microcrystalline texture, and alkali-feldspar rhyolite, with porphyritic texture, matrix phaneritic (spherulitic and granofírica). Zircons of alkali feldspar rhyolite were selected for dating through evaporation method Pb (Pb-Pb method Zircon). Among the crystals analyzed, four showed an average age of 1874 ± 3 Ma, interpreted as the crystallization age of the body. The age obtained is similar to previous work in the area of Água Azul do Norte, suggesting therefore a contemporaneity between these various events, as well as between them and the Paleoproterozoic granites of anorogenic Granites Seringa and São João and even possibly correlated to Paleoproterozoic granites anorogenic and dykes belonging to Jamon suite (1.88 Ga).
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