Interpreting the ice dynamics and palaeogeography of Cryogenian - Cambrian glacial geology of China

埃迪卡拉纪到寒武纪的罗泉组(&gt；521 Ma，北中国)由保存完好的亚冰川条纹路面组成，上面覆盖着一系列冰下到冰川沉积。该项目旨在更好地了解其沉积背景和过程，以及其冰川冰的特征、范围和动态。这将通过利用成熟的地质技术进行露头调查来实现，例如测量剖面、测绘和沉积构造定位。这项研究将提高对我们过去的地球如何工作的理解：(1)这种古老岩石上的条纹路面在全球范围内很少见，罗泉组的条纹路面是前寒武纪最好的例子之一。它们提供了有关上覆古冰的重要信息，但关于罗泉人行道的数据很少，而且受到人为破坏的威胁；(2)全球是否存在寒武纪冰川地层仍未得到证实；(3)罗泉组沉积时，北中国克拉通处于中低纬度。在上一次寒武纪期间，这些纬度存在海平面冰，这被认为是泛全球“雪球地球”冰川的诊断证据。罗泉组冰筏碎屑的海平面沉积背景将显著改变对埃迪卡拉纪到寒武纪全球气候的理解。这些矿床的研究将通过与美国中国西北部寒武纪地层保存的条纹面和奥地利现代地表的比较来补充。

The Ediacaran to Cambrian aged Luoquan Formation (> 521 Ma, North China) comprises exquisitely preserved subglacially striated pavements, overlain by a range of subglacial to proglacial deposits. This project seeks to better understand its depositional context and processes, along with the character, extent and dynamics of its glacial ice. This will be achieved through outcrop investigation using well-established geological techniques, such as measured sections, mapping and sedimentary structure orientation. This study will improve understandings of how our past planet worked: (1) Striated pavements are globally rare upon such ancient rocks and those of the Luoquan Formation are amongst the best Precambrian examples. They yield important information about the overlying ancient ice, yet scant data is published on the Luoquan pavements and they are imminently threatened by anthropogenic destruction; (2) Whether any glacial strata of Cambrian age occur globally remains unconfirmed; (3) The North China Craton was at mid to low latitudes during Luoquan Formation deposition. The presence of sea-level ice at these latitudes during the preceding Cryogenian Period is considered diagnostic evidence of pan-global "Snowball Earth" glaciation. A sea-level depositional context for ice rafted debris of the Luoquan Formation would significantly change understandings of Ediacaran to Cambrian global climate. Study of these deposits will be complimented by comparison to preserved striated surfaces from Cryogenian strata of NW China, USA and modern surfaces of Austria.