Comprehensive U-Pb detrital zircon geochronology of Ediacaran sandstones from Oman indicates that they originated from Neoproterozoic basement with a peak magmatic age of ca. 850–780 Ma (Tonian), with lesser Paleoproterozoic and Ediacaran sources and renewed magmatic input starting at ca. 550 Ma. Comparison with detrital zircons from the Arabian-Nubian and NW Indian Shields supports an eastern Gondwana affinity for the Ediacaran succession of Oman. Tonian basement sediment sources are present in Oman. Sources for older Paleoproterozoic zircons (ca. 2500 and 1800 Ma) are not found in Oman but are known from the cratonic Indian Shield. The signal of the main magmatic events of the juvenile Arabian-Nubian Shield, peaking at ca. 640–620 Ma, is rare or absent in the Ediacaran rock succession of Oman. However, deformed Ediacaran clastic units with an Arabian-Nubian Shield affinity occur in western Oman. Influx of latest Ediacaran–early Cambrian zircons (550–525 Ma) is interpreted as due to final Cambrian Angudan/Malagasy orogeny-related magmatism.These results, together with new ages for volcano-sedimentary terranes in the subsurface of SW Oman and seismic observations, support the interpretation that the Ediacaran succession of Oman was deposited along the western, passive margin of the Greater Indian Shield, on the eastern (east and west in this paper refer to present-day coordinates) side of the Mozambique Ocean. Oman then collided with the Arabian-Nubian Shield in the early Cambrian, when the Angudan/Malagasy orogeny led to final consolidation of Gondwana. Our data support the inference that the youngest and final suture between the Indian and Arabian Shields lies in the subsurface of Oman along the early Cambrian western deformation front.

中文翻译：

---

阿曼是冈瓦纳东部埃迪卡拉纪的一部分


对阿曼埃迪卡拉系砂岩进行的综合 U-Pb 碎屑锆石年代学表明，它们起源于新元古代基底，峰值岩浆年龄约为 1000 年。 850–780 Ma（托尼安期），古元古代和埃迪卡拉源较少，并且从大约 1000 Ma 开始重新注入岩浆。 550马。与阿拉伯-努比亚地盾和西北印度地盾的碎屑锆石的比较支持冈瓦纳东部与阿曼埃迪卡拉序列的密切关系。阿曼存在托尼安基底沉积物来源。阿曼未发现较古老的古元古代锆石（约 2500 和 1800 Ma）的来源，但已知来自克拉通的印度地盾。幼年阿拉伯-努比亚地盾的主要岩浆事件的信号，在大约 10 世纪达到顶峰。 640–620 Ma，在阿曼的埃迪卡拉岩层序中很少见或不存在。然而，具有阿拉伯-努比亚地盾亲和力的变形埃迪卡拉碎屑单元出现在阿曼西部。最新埃迪卡拉纪-早寒武世锆石（550-525 Ma）的涌入被解释为由于最终寒武纪安古丹/马达加斯加造山运动相关的岩浆作用。这些结果以及阿曼西南部地下火山沉积地体的新年龄和地震观测，支持这样的解释：阿曼的埃迪卡拉序列是沿着大印度地盾的西侧被动边缘沉积的，位于莫桑比克洋的东侧（本文中的东侧和西侧指当今的坐标）。随后，阿曼在寒武纪早期与阿拉伯-努比亚地盾相撞，当时安古达/马达加斯加造山运动导致了冈瓦纳大陆的最终巩固。我们的数据支持这样的推论：印度地盾和阿拉伯地盾之间最年轻和最终的缝合线位于阿曼地下，沿着早寒武世西部变形前缘。