The immature lateritic profile Abel Figueiredo is located in the region Paragominas - Rondon do Pará in southern Pará State, that stands out by occurrence of lateritic formations, With large deposits of bauxite and kaolin associates, linked to mature lateritic profiles. Immature lateritic formations also stand out in this region, with the exhibition of excellent immature profiles during the construction of the BR-222. At km 137 of this highway, 9 km northeast of the city of Abel Figueiredo is located lateritic profile object of study. From it, 10 samples were collected, which were described, photographed, prepared and submitted to mineralogical analysis by XRD, optical and eletronic microscopy; and chemical analysis aiming to develop a textual study, mineralogical and chemical in detail the immature lateritic profile and coverage, and to characterize the content of heavy minerals and anatase to allow exercise discussions on the source rock and evolution processes that profile. This consists of a sequence of three horizons: the iron-aluminous crust partially dismantled at the base, the crust is dark reddish brown, microporous, cavernous and shows ferruginous nodules of iron oxy-hydroxides; the horizon spherolithic the nodular superimposed is represented by spheroliths dark reddish brown surrounded by clay matrix; the clay cover at the top is represented by a yellow silty-clay material, homogeneous considered latosol. The mineralogy of the immature profile and coverage is represented by hematite, goethite, kaolinite, quartz, accessory minerals include anatase and heavy minerals (zircon, rutile, tourmaline, kyanite, staurolite and opaque). However, these differ in content, ranging second lithology and even horizons. The chemical composition reinforces mineralogical data, confirming the domain SiO2, Fe2O3, Al2O3 and TiO2. Therefore, the mineralogical composition and the distribution of the main chemical components and assembly of heavy minerals (show domain minerals ultra stable) are compatible with the lateritic evolution, equivalent to lateritic profiles better distributed in the Amazon, known as immature.
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