The lateritics iron crusts are well distributed in Amazon and its majority ores results of laterizations processes. In Canaã domain of the Carajás Province, lateritics formations are very common in lowered lands. Therefore paleoenvironmental importance, this research aims to evaluate how paleoclimatic changes influenced this area and its surroundings. Samples of iron crusts were collected, described, photographed, prepared and submitted to mineralogical analysis by optical and electronic, XRD, FTIR, differential thermal analysis (DTA) and thermogravimetry (TGA) and chemical analysis aiming to characterized the mesoscopics, microscopics, mineralogicals and chemicals. The crusts are massive to slightly porous, and porous, rarely nodular, reddish-brown to ochre. Hematite, goethite and kaolinite are main minerals. Through the optical microscopy, the general aspect comprises cryptocrystalline plasma hematitic, goethitic and kaolinitic which cements nodules, pisolites and, sometimes, fractured and/or corroded quartz grains. Mostly occur dissolution pores quartz grains. Chemical analysis confirms SiO2, Al2O3 e Fe2O3 domains. Analysis of major and minor elements, trace elements and rare earths allowed to identify crusts derived from acidic rocks, with more aluminossilicates, and intermediate to basic rocks. The mineralogical and chemical composition is compatible with the Amazon immature lateritic profiles, formed during humid and hot climate, with alternation between semiarid periods and savannah coverage in Pleistocene.
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