The geochemistry of phosphorus in different granite suites of the Western Carpathians, Slovakia: the role of apatite and P-bearing feldspar

摘要: The geochemical behaviour of phosphorus in granites, coupled with compositional variations apatite, discriminate the different genetic suites Variscan granitic rocks West-Carpathian orogenic belt. Meso-Variscan mostly Stype affinity, show a good correlation between SiO2 and P2O5, decreasing amounts P poorly moderated fractionated increasing most evolved late differentiation products. aluminium saturation index (ASI) correlates negatively bulk contents I-type positively S-type granites. content alkali feldspar (mainly Kfs) is usually very low (typically <0.05 wt.% P2O5), or not detected slightly differentiated In lateVariscan I/S-type granitoids, hosted mainly early-magmatic but present also K-feldspar (up to 0.15 P2O5) that formed from residual melts. postorogenic occurs (f0.3 minor proportion primary apatite. Clusters small secondary apatite grains distinctive composition are distributed post-orogenic This has post-magmatically released P-rich during temperature, by reaction fluid rich volatiles (including F B), earth metals. A-type granites have lowest contents. Consequently, phosphate minerals relatively rare this granite type, negligible P2O5 Except for Sr, element partly correlate their host reflect some thermodynamic properties melt. Mn increase peraluminous character melt fO2 so significantly higher than Apatite enriched Fe HREE, reflecting HREE type. specialized Yand HREE. general, Cl S basic members affinity rocks. D 2004 Elsevier B.V. All rights reserved.