In the eastern region of the Araguaia Belt (AB), in Tocantins State, four relatively small granitic bodies are identified: Ramal do Lontra (GRL), Presidente Kennedy (GPK), Barrolândia (GBR) e Santa Luzia (GSL). These rocks represent the record of an important granitogenesis event that is related to the evolution of the AB at the later Neoproterozoic. The few geological data on these bodies were poorly organized which precluded an integrated understanding and the correlation with other outcropping areas. This magmatism is not spatially very representative, but it is important due to the relationship of the granitic emplacement with the main phase of the regional metamorphism. This work is focused on the petrological and geochronological interpretation of granitic magmatism of the AB, especially on the petrographic and geochemical characterization of the main bodies, definition of ages of the magmatic episodes by zircon U-Pb dating and investigation of sources and time of crustal residence by TDM model ages (Sm-Nd) and Nd values. The studied bodies comprise stocks with slightly oval shapes and size that varies from 3 to 6 km on the major axis and 2-8 km on the smaller one, which are emplaced on micaxistes and quartzites of the Estrondo Group. In field stage, some important features were noted, such as the lack of the contact metamorphism and xenoliths on the country rocks, as well as the lack of the cooling borders, presence of granitic portions on the country rocks and the structural concordance between the foliations of the country rocks and the granitic body. The rocks were classified as two-mica meta-granites with low mineralogical variation, low mafic mineral content (<6%), hololeucocratic, medium grained and equigranular features, and granoblastic and relic granular hypidiomorphic textures. On the QAP diagram, the GRL, GBR and GSL plotted on the monogranite field or on the limits between the monzogranite and granodiorite fields, whereas, the GPK felt on the granodiorite field. The essential mineralogical content is formed by oligoclase, quartz and microcline, followed by biotite and muscovite. The accessory minerals are represented by apatite, zircon, allanite, garnet, monazite and opaque minerals. The granitic rocks are geochemically similar with SiO2 content from 71% to 74%, and Al2O3 between 13% and 15%. The Na2O and K2O contents are slightly higher in the GRL and GPK, which reflect on the A/CNK ratio, plotting on the peraluminous field. The low content of MgO, Fe2O3Total and CaO indicate these rocks are low fractionated. The trace elements also pointed out small compositional variations on the rocks of the different bodies. The REE patters demonstrated a medium to strong fractionation of the light REE in relation to the heavy REE, showing (La/Yb)N values between 11.8 and 72.8 and week Eu anomalies (Eu/Eu* = 0.5-1.3). The zircon U-Pb dating by SHRIMP reveled ages of 542.7 ± 1.9 Ma (GPK), 541.5 ± 1.8 Ma (GBR) and 546.4 ± 2.3 Ma (GSL). These ages were interpreted as zircon crystallization at the later Neoproterozoic. The age obtained for the GRL was slightly older (615,7 ± 26 Ma) with a higher MSWD errors. The Sm-Nd isotopic results for the four bodies reveled TDM model ages between 1.69 and 1.84 Ga and Nd values from -12.18 to -6.21. On the Nd versus time diagram, the plots indicate a dominantly Statherian crustal sources for the parental magmas. The integrated data analysis allows us to suggest that the granitic bodies are correlated, which their origin is associated to a same granitogenesis event. The U-Pb ages between 541 and 546 Ma, interpreted as crystallization of the GPK, GBR and GSL, are related to the main metamorphic phase of the AB. The emplacement of this bodies is associated to the orogenic collisional phase of the AB at the later Neoproterozoic. The Sm-Nd data suggest that the studied rocks were generated by anatexia of at least two different sources, which favored the aggregation of granitic melts, rising and late emplacement of these magma at the main phase of the Araguaia Belt.
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