Abstract Thick Neoproterozoic rift sequences along the western margin of the East European Craton (EEC) are classically attributed to rifting leading to break-up of super-continent Rodinia/Pannotia. Rifting was associated with intense, mainly mafic, volcanism, known as the Volyn Series, in the Lublin-Podlasie Basin (LPB) and in the Orsha-Volyn Aulacogen. Legacy deep boreholes in Poland provide continuous section through the volcanic series. Zircon from nine samples of tuff layers interbedded with basalt, from four boreholes, were dated with the U–Pb method with SHRIMP. The samples contain syn-eruptive zircons, together with zircon recycled from previous ash falls and zircon from the surrounding Proterozoic basement. The youngest volcanic zircon cluster from each sample of the studied tuff samples yielded concordia ages stratigraphically consistent, which document eruption events that took place between 567.1 ± 4.7 Ma and 551.0 ± 4 Ma. The most intense development of lavas and pyroclastics took place at ca. 557–555 Ma and ca. 567–560 Ma. Older volcanogenic zircon grains, inherited from previous phases of volcanic activity, preceding actual eruptions, were are dated at 588.0 ± 8 Ma to 580 ± 8.1 Ma. Age spectrum of xenocrysts zircon grains, inherited from the crystalline basement rocks of the LPB, ranges from ca. 1830 Ma to ca. 1480 Ma, coherent with the known late Paleoproterozoic and Mesoproterozoic age of crust-forming events in the western part of the EEC. The late Ediacaran syn-rift igneous activity in the LPB continued over a time span of approx. 37 My. It developed along both the SW margin of emerging Baltica and in the western the Orsha-Volyn Aulacogen. The study area was located at the intersection of these regional structures, being thus a site of development of an incipient triple junction, related to Rodinia/Pannotia break-up. Further extension along the SW margin of Baltica led to its separation from the plate adjacent to the west, and to the subsequent development of continental passive margin. Final emergence of Baltica, as an individual palaeocontinent, took place at ca. 550 Ma.

中文翻译：

---

东欧克拉通西坡沃伦火山复合体的年代学——与新元古代裂谷和 Rodinia/Pannotia 分裂的相关性

摘要 沿东欧克拉通 (EEC) 西缘的厚新元古代裂谷序列经典地归因于裂谷导致超级大陆 Rodinia/Pannotia 的破裂。Lublin-Podlasie 盆地 (LPB) 和 Orsha-Volyn Aulacogen 中的裂谷作用与强烈的、主要是基性的火山活动有关，被称为 Volyn 系列。波兰遗留的深钻孔提供了贯穿火山系列的连续剖面。来自四个钻孔的九个与玄武岩互层的凝灰岩层样品的锆石用 U-Pb 方法和 SHRIMP 测定了年代。样品包含同步喷发的锆石，以及从先前火山灰坠落中回收的锆石和来自周围元古代基底的锆石。来自研究的凝灰岩样品的每个样品中最年轻的火山锆石簇产生了在地层学上一致的协和岩年龄，记录了发生在 567.1 ± 4.7 Ma 和 551.0 ± 4 Ma 之间的喷发事件。熔岩和火山碎屑最强烈的发展发生在大约。557-555 马和约。567–560 马。较早的火山成因锆石颗粒，继承自火山活动的先前阶段，在实际喷发之前，其年代为 588.0 ± 8 Ma 至 580 ± 8.1 Ma。外晶锆石颗粒的年龄谱，从 LPB 的结晶基底岩继承，范围从约 1830 马到大约 1480 Ma，与已知的 EEC 西部地壳形成事件的晚古元古代和中元古代时代相一致。LPB 中晚期埃迪卡拉纪同裂谷火成岩活动持续了大约 20 年的时间跨度。37 我的。它沿着新兴的波罗的海的西南边缘和奥尔沙-沃伦 Aulacogen 的西部发展。研究区位于这些区域结构的交汇处，因此是与 Rodinia/Pannotia 分裂有关的早期三重连接的发展地点。沿着波罗的海西南边缘的进一步延伸导致其与西部相邻的板块分离，并导致大陆被动边缘的后续发展。作为一个单独的古大陆，波罗的海的最终出现发生在大约。550 马。