Abstract
One hundred and twenty three analyses for rocks, matrixes of porphyritic rocks and accessory minerals (sphene, zircon, tourmaline) from crustal (including tourmaline granites), calc-alkaline and rapakivi granites from the State of Sao Paulo, SE Brazil, are presented, compared and discussed. By zircon typology, these granites belong to the lineages 3,4a, 4b, and 5 in Pupin's (1980) classification. The data show large influence of sphene, zircon, and tourmaline in the shape of the whole rock REE pattern of the, respectively, crustal/calc-alkaline, rapakivi and tourmaline granites. The matrixes of porphyritic rocks show higher REE contents than the whole rocks; the zircons from different granitoids lineages have REE contents proportional to those of the host rocks, and in the tourmaline granites the REE contents reflect clearly the modal percentage of this accessory mineral. The mean REE contents in these rocks increase progressively along the lineage sequence 3, 4a, 4b and 5. The data also show the active participation of accessory minerals in the fractional crystallization of granitic magmas and that the interpretation of the REE pattern of granitoids is a complex task which requires not only whole rock data but also those of REE concentration in accessory minerals or chemical data which allow to trace their behaviour during magma evolution.
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