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

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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.