Metabasic rocks of the ophiolitic sequences of the Glockner Nappe and Eclogite Zone in the south-central Tauern Window, Austria, reveal important insights into rifting and spreading of the Alpine Tethys. U–Pb dating of magmatic zircons yields a concordant 157 ± 2 Ma crystallization age for the precursor of a coarse-grained metagabbro from the Glockner Nappe. The Late Jurassic intrusion age is coeval with mafic plutonic activity in the Western and Central Alps. Although Penninic ophiolitic sequences in tectonic windows of the Eastern Alps are usually disrupted, an ocean–continent transition setting can be reconstructed for the Glockner Nappe, similar to many ophiolites in the Liguria–Piemont domain in the Western and Central Alps. Together, these observations strongly suggest a formation in the Liguria–Piemont branch of the Alpine Tethys and are inconsistent with a formation in the Valais domain. This finding has important implications for paleogeographic reconstructions of the Penninic realm in the Eastern Alps. Whereas the Glockner Nappe metagabbro and metabasalts clearly reveal their depleted mantle origin, the metabasic rocks of the Eclogite Zone record a more complex formation history involving depleted mantle melting and crustal assimilation in a continental margin setting.

奥地利 Tauern Window 中南部格洛克纳推覆岩和榴辉岩带蛇绿岩层序的变基性岩石揭示了对高山特提斯山脉的裂谷和扩张的重要见解。岩浆锆石的 U-Pb 测年得出格洛克纳推覆岩粗粒变辉长岩前驱体的一致 157 ± 2 Ma 结晶年龄。晚侏罗世侵入时代与西部和中部阿尔卑斯山的镁铁质深成岩活动同时期。尽管东阿尔卑斯山构造窗口中的 Penninic 蛇绿岩序列通常被破坏，但可以为格洛克纳推覆重建海洋 - 大陆过渡环境，类似于西部和中部阿尔卑斯山的利古里亚 - 皮埃蒙特区域的许多蛇绿岩。一起，这些观察结果强烈表明高山特提斯山脉的利古里亚-皮埃蒙特分支中存在地层，与瓦莱州地区的地层不一致。这一发现对东阿尔卑斯山 Penninic 领域的古地理重建具有重要意义。Glockner Nappe 变长岩和变玄武岩清楚地揭示了它们的枯竭地幔起源，榴辉岩带的变质岩记录了更复杂的形成历史，包括在大陆边缘环境中枯竭地幔熔融和地壳同化。