Miller C, Thöni M, Goessler W, Tessadri R
Institut für Mineralogie und Petrographie, Universität Innsbruck, Innrain 52, A-6020 Innsbruck, Austria.
Department für Lithosphärenforschung, Geozentrum, Althanstrasse 14, A-1090 Wien, Austria.
Lithos. 2011 Jul;125(1-2):434-448. doi: 10.1016/j.lithos.2011.03.003.
The northern part of the Karawanken plutonic belt is a gabbro-granite complex located just north of the Periadriatic lineament near the Slovenian-Austrian border. Petrographic and geochemical studies of the Eisenkappel intrusive complex indicate that this multiphase plutonic suite developed by a combination of crystal accumulation, fractional crystallization and assimilation processes, magma mixing and mingling. The mafic rocks are alkaline and have within-plate geochemical characteristics, indicating anorogenic magmatism in an extensional setting and derivation from an enriched mantle source. The mafic melts triggered partial melting of the crust and the formation of granite. The granitic rocks are alkalic, metaluminous and have the high Fe/Fe + Mg characteristics of within-plate plutons. Temperature and pressure conditions, derived from amphibole-plagioclase and different amphibole thermobarometers, suggest that the analysed Eisenkappel gabbros crystallized at around 1000 ± 20 °C and 380-470 MPa, whereas the granitic rock crystallized at T ≤ 800 ± 20 °C and ≤ 350 MPa. Mineral-whole rock Sm-Nd analyses of two cumulate gabbros yielded 249 ± 8.4 Ma and 250 ± 26 Ma (εNd: + 3.6), garnet-whole rock Sm-Nd analyses of two silicic samples yielded well-constrained ages of 238.4 ± 1.9 Ma and 242.1 ± 2.1 Ma (εNd: - 2.6).
卡拉万肯深成岩带的北部是一个辉长岩 - 花岗岩杂岩体，位于斯洛文尼亚 - 奥地利边境附近的佩里亚德里亚断裂带以北。对艾森卡佩尔侵入杂岩体的岩石学和地球化学研究表明，这套多阶段深成岩组合是通过晶体堆积、分离结晶和同化作用、岩浆混合和混染等过程形成的。镁铁质岩石为碱性，具有板内地球化学特征，表明在伸展环境下的非造山岩浆作用，且源自富集地幔源区。镁铁质熔体引发了地壳的部分熔融和花岗岩的形成。花岗岩类岩石为碱性、准铝质，具有板内深成岩体的高Fe/Fe + Mg特征。由角闪石 - 斜长石和不同角闪石温度计得出的温度和压力条件表明，分析的艾森卡佩尔辉长岩在约1000 ± 20°C和380 - 470MPa的条件下结晶，而花岗岩类岩石在T ≤ 800 ± 20°C和≤ 350MPa的条件下结晶。对两块堆积辉长岩进行的矿物 - 全岩Sm - Nd分析得出年龄为249 ± 8.4Ma和250 ± 26Ma（εNd：+3.6），对两块硅质样品进行的石榴石 - 全岩Sm - Nd分析得出年龄为238.4 ± 1.9Ma和242.1 ± 2.1Ma（εNd：-2.6），年龄约束良好。
