The Tartarugal Grande Complex is represented by a high rock metamorphic association degree of Paleoproterozoic with Archean relics, which occurs on the northern edge of the Amapá Block, in the context of Maroni-Itacaiúnas Province, southeast of the Guyana Shield. In this region, the Tartarugal Grande Complex meets gneiss and granulite rocks, dominated enderbitic and charnockitics types, forming elongated rocks and marked by lineament NW-SE direction, characterized as transcurrent and thrust shear zones. This unit is formed by an intricate combination of high-grade metamorphic rocks and this study aimed to characterize these rocks petrographically, geochemically and geochronology discussing the processes in this metamorphic terrain. Petrographic analyzes identified five types of rocks classified as charnockitic granulite, charnoenderbitic granulite, enderbitic granulite, mafic granulite and leucogneisses Migmatization features as neossomes also present in felsic granulites (charnockitics, enderbitics and charnoenderbitics) and gneisses. The felsic granulites are the dominant rocks in the area, while the mafic granulites occur as smaller rocks, metric dimensions, embedded in other granulites and gneisses. The leucognaisses are commonly associated with enderbitic/charnockitic granulites, showing sudden contacts with these rock types. The lithogeochemical studies in these rocks indicated that the Tartarugal Grande Complex predominance of acid rock with silica content between 61 and 75%, and peraluminous, due to the presence of minerals such as biotite, garnet and cordierite. The mafic granulites are dominantly basic types (SiO2 between 48 and 55%) with high Fe2O3 levels (12 to 26%), MgO (5 to 19%) and CaO (2 to 12%). In geochemical classification diagrams felsic granulites and leucognaisses are located in granite field, while the mafic granulites plots in gabbro field. In AFM diagram, the felsic granulites have characteristics of collisional calc-alkaline suite and mafic granulites are basaltic types of tholeiitic suite. In the multi-element diagrams felsic granulites out more significant anomalies of Ti and P, in addition to the strong negative anomaly of Nb, characteristic of subduction environments. The mafic granulites shows, mostly signed with sub-horizontal pattern. For the rare earth elements (REEs), felsic granulites at moderate enrichment of light REEs, for heavy REEs with low Eu anomalies (ratio Eu/Eu* = 0.19 to 5.51). The mafic granulites had a lower degree of fractionation and recorded insignificant Eu anomalies (ratio Eu/Eu* = 0.44 to 1.07). The leucogneisses shows very similar to the felsic granulites signature, but have different genesis. In the discrimination diagrams of tectonic environments, it was established magmatic arc environment related to the subduction zone. U-Pb geochronological analyses in situ zircon crystals by LA-ICP-MS done in charnoenderbitic granulite, enderbitic granulite, garnet–biotite leucogneisse and charnockitic granulite, provided average ages of 2045 ± 14 Ma, 2084 ± 7.9 Ma, 2617 ± 25 Ma and 2671 ± 10 Ma respectively. These results represent the formation age of the protoliths of these rocks. Ages obtained by other studies by Sm-Nd whole rock-garnet between 2.02 and 1.98 Ga indicate a high grade metamorphic event near the age placement of plutons. The parageneses characteristics of the rocks found in the search area are represented by: mesopertitic Mc + Qtz + Pl + Opx + Bt (charnockitic granulite); Pl + Qtz + mesopertitic Mc + Opx ± Bt (charnoenderbitic granulite); Pl + Qtz + mesopertitic Mc + Opx + Bt ± Cpx ± Hbl (enderbitic granulite); Pl (An60) + Opx + Cpx + Hbl (mafic granulite) and; Qtz + Mc + Pl ± Bt ± Grt ± Crd (leucogneisses) and these associations indicate that the rocks was subjected to conditions of regional metamorphic granulite facies in temperature conditions between 780 and 850°C and pressure between 5 and 7 kbar. Not extensive meltings (anatexis) are also common in the area where masses of sienogranitics compositions originated under high temperature conditions from granulites and gneisses. In addition, characteristics indicative of cooling were found in these rocks, such as partial or total replacement of pyroxene by biotite and/or hornblende, garnet by biotite and cordierite by pinit. Thus, in accordance with results of studies already developed in the area and indicated by datings performed in this present study, it was concluded that the Tartarugal Grande Complex comprises rocks that were involved during magmatic events in Neoarchean and Rhyacian, followed by high-grade metamorphism in Paleoproterozoic end and related thermo-tectonic Transamazonian event. This event deformed pre-existing types and rebalanced minerals rocks, resulting in a complex association of granulites and gneisses with different ages, origins and deformation intensities.
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