We document structural, geochemical, petrological and ⁴⁰Ar/³⁹Ar geochronological data performed on Variscan eclogites from the Argentera–Mercantour Massif, southwestern Alps. Based on the high-resolution field mapping, we present new eclogite occurrences and discuss the relationships between eclogites and surrounding migmatites. We recognized for the first time preserved eclogite facies assemblages. Trace elements and REE patterns establish that eclogites protoliths are MORBs contaminated by continental crust. Standard thermobarometry and thermodynamic modeling are consistent with P–T values of 640–740 °C for 1.5 ± 0.25 GPa, coherent with paleo-geotherms predicted for warm subduction of oceanic crust. We interpret these eclogites as a dismembered cryptic suture zone. ⁴⁰Ar/³⁹Ar dating on amphiboles yields an age of 339.7 ± 12 Ma for eclogite retrogression under amphibolite facies conditions. All these data are combined to link the Argentera–Mercantour Massif in the tectonic framework of both pre-Mesozoic Alpine basement and European southern Variscides.

我们记录了在西南阿尔卑斯山的阿根廷－Mercantour地块的Variscan榴辉岩上进行的结构，地球化学，岩石学和⁴⁰ Ar / ³⁹ Ar地球年代学数据。基于高分辨率场图，我们提出了新的榴辉岩事件，并讨论了榴辉岩与周围的辉贵岩之间的关系。我们首次认识到保存的榴辉岩相组合。痕量元素和REE模式确定了榴辉岩原石是被大陆壳污染的MORB。标准热压法和热力学模型与P – T一致1.5±0.25 GPa时，温度为640–740°C，与古地热相一致，可预测海洋地壳的热俯冲。我们将这些榴辉岩解释为肢解的神秘缝线区。在闪石相条件下，辉绿岩倒退时，闪石上的⁴⁰ Ar / ³⁹ Ar年龄为339.7±12 Ma。所有这些数据结合起来，在中生代之前的高山基底和欧洲南部的Variscides的构造框架中将阿根廷－Mercantour地块联系起来。