The provenance of Triassic Vieux Emosson Formation, autochthonous sediments of the Aiguilles Rouges massif (External Alps), was determined from U–Pb ages of detrital zircons. In addition, two samples of Late Carboniferous sandstones from the Salvan‐Dorénaz basin were included to extend the database of potential source rocks. Overall, age data from the four samples are largely comparable, each with a wide range of ages, indicating similar source rocks. The compositionally and texturally immature strata of the Vieux Emosson Formation suggest a local sediment source. However, not all detrital zircons can be accounted for by the ages of the local polymetamorphic pre-Mesozoic basement, which consists mainly of paragneiss, Ordovician orthogneiss and Late Carboniferous, Variscan-related, magmatic and sedimentary rocks. Ordovician zircons were common in the samples, but Late Carboniferous zircons were only abundant in one sample. Early Cambrian and older zircons were likely recycled from the paragneiss. Recycled zircons primarily represent Cadomian orogenic events (~ 550–650 Ma); older zircons are from eastern Gondwana and West African craton sources. Abundant late Cambrian (~ 500 Ma) and Silurian (~ 425 Ma) zircons likely represent Cadomian rifting and the magmatic events that produced the Ordovician orthogneiss, respectively. Permian zircons were only found in one Triassic sample, and are possibly related to magmatic activity associated with post-Variscan extension. The age data of the detrital zircons in the Triassic Vieux Emosson Formation and in the sandstones from the Late Carboniferous Salvan-Dorénaz basin indirectly dates the source rocks and for the first time confirms Cadomian basement in the Aiguilles Rouges massif. Source rocks for the Silurian, Permian, and to a lesser degree, late Cambrian zircons are not documented in the local basement, and either have been eroded away or are now located to the southeast beneath Penninic nappes.

中文翻译：

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瑞士阿尔卑斯山西部三叠纪砂岩的U–Pb锆石来源：对大地构造史的影响

根据碎屑锆石的U–Pb年龄确定了三叠纪老Emosson组（Aiguilles Rouges地块（外部阿尔卑斯山）的本土沉积物）的起源。此外，还包括了Salvan-Dorénaz盆地的两个晚石炭纪砂岩样品，以扩展潜在烃源岩的数据库。总体而言，这四个样品的年龄数据在很大程度上具有可比性，每个年龄段范围都很大，表明烃源岩相似。Vieux Emosson组的成分和质地上不成熟的地层表明是局部沉积物来源。然而，并不是所有碎屑锆石都可以由当地多变质前中生代基底的年龄来解释，该基底主要由帕勒尼切斯，奥陶纪正长片岩和晚石炭纪，与瓦里斯坎有关的岩浆和沉积岩组成。奥陶纪锆石在样品中很常见，但晚石炭纪锆石仅在一个样品中丰富。早期的寒武纪锆石和较老的锆石很可能是从paragneiss回收的。回收的锆石主要代表卡多巴造山事件（〜550–650 Ma）。较老的锆石来自冈瓦纳东部和西非克拉通来源。晚寒武纪（〜500 Ma）和志留纪（〜425 Ma）的大量锆石可能分别代表了卡多夫裂谷和产生奥陶纪正长片岩浆的岩浆事件。二叠纪锆石仅在一个三叠纪样品中发现，可能与后Variscan延伸有关的岩浆活动有关。三叠纪维埃克斯·埃莫森组和晚石炭纪Salvan-Dorénaz盆地砂岩中碎屑锆石的年龄数据间接记录了烃源岩的日期，并首次证实了Aiguilles Rouges地块的Cadomian基底。志留纪，二叠纪以及稍次的寒武纪锆石的烃源岩在当地地下室中没有记载，或者已经被侵蚀掉，或者现在位于Penninic尿布下面的东南部。