One of the most complete Permian-Triassic fluvial sequences of the Beacon Supergroup, characterizing the infilling of the Transantarctic Basin, is recorded in the Allan Hills in Victoria Land (Antarctica). The multidisciplinary provenance approach carried out in this study includes UPb analysis on detrital zircons, chemistry on detrital mineral phases (garnet and white mica), and sandstone petrography. These, coupled with the data regarding the stratigraphic/sedimentological framework, provide a reconstruction of the geological history of the Permian-Triassic portion of the Beacon Supergroup, showing shifting clastic provenance from different source rocks. Results obtained from this integrated study support a source for the Permian Weller Coal Measures from the local basement, made up of very low- to high grade metamorphic rocks. A compositional shift is recorded with the Lower Triassic Feather Conglomerate, mainly linked with changes in the fluvial style, likely associated with tectonic activity. The Middle to Upper Triassic Lashly Formation shows the main provenance change, supporting a distal source region: the fluvial system received a volcanoclastic input derived from the Permian-Triassic arc located to the east of the basin. The compositional and provenance variations, together with paleocurrent indicators, compared to the coeval units in the central Transantarctic Mountains, allow the reconstruction of the basin evolution and of the changing clastic drainage patterns. Data support the occurrence of articulated sub-basins where alluvial sedimentation settled, in which a morphological-structural divide was represented by the Ross High, separating during the Permian up to the Early Triassic the Victoria Land sub-basin from the main Transantarctic Basin. According to the changed composition of the Lashly Formation sandstones, it appears that in the Middle/Late Triassic, the Ross High was not more a morphological barrier, and that the Victoria Land sub-basin was joined with the Transantarctic foreland Basin.

中文翻译：

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维多利亚地（南极洲）二叠纪-三叠纪河流序列的多代理碎屑研究：对冈瓦纳盆地演化的影响

维多利亚地（南极洲）的艾伦山记录了灯塔超群最完整的二叠纪-三叠纪河流序列之一，其特征是横贯南极盆地的填充。本研究采用的多学科来源方法包括碎屑锆石的 UPb 分析、碎屑矿物相（石榴石和白云母）的化学以及砂岩岩相学。这些数据与地层/沉积学框架的数据相结合，重建了灯塔超群二叠纪-三叠纪部分的地质历史，显示了来自不同烃源岩的碎屑物来源的变化。这项综合研究获得的结果支持二叠纪 Weller 煤系的来源来自当地基底，由极低品位到高级变质岩组成。下三叠世羽毛砾岩的成分发生了变化，主要与河流样式的变化有关，可能与构造活动有关。中上三叠统Lashly组显示了主要物源变化，支持了远端源区：河流系统接收了来自盆地东部二叠纪-三叠纪弧的火山碎屑输入。与横贯南极山脉中部的同时代单元相比，成分和物源变化以及古水流指标可以重建盆地演化和不断变化的碎屑排水模式。数据支持冲积沉积物沉积的铰接次盆地的出现，其中以罗斯高地为代表的形态-结构分界线，在二叠纪至早三叠世期间将维多利亚地次盆地与主要的跨南极盆地分开。根据Lashly组砂岩成分的变化，在中、晚三叠世，罗斯高地不再是一个地貌屏障，维多利亚地次盆地与横贯南极前陆盆地相连。