The samples analysed are examples of magma-sediment interaction and were investigated to further understand the mixing fabrics in 3D. The research is being undertaken by PhD student Rebecca Miles (USW) and supervised by Dr Ian Skilling and Professor Duncan Pirrie (USW). The samples are from the Gwna Group Melange (Monian Super Group) spanning the Precambrian Ediacaran Period (635 Ma) to early Cambrian Comley series (510 Ma), which crops out as part of the iconic and well documented succession on Anglesey, North Wales. This unit offers clear evidence of spectacular interaction of basaltic magma and seafloor sediment on the metre to millimetre scale (i.e. peperite generation), which has been recognized here for the first time. The age of the studied limestones is poorly known but other Gwna Group limestone megaclasts on the island which are up to hundreds of metres in size, have been documented using strontium isotope chemostratigraphy as having a Neoproterozoic depositional age between early Cryogenian (c. 800 Ma) and late Tonian (860 Ma) (Horák & Evans, 2010). 10 field samples were selected from the suite of collected field samples for 3D imaging using microCT. The combined results with optical imaging will allow the fine resolution of the magma-sediment interaction to be imaged in 3D for the first time It is anticipated that the results arising from this study, which would form part of Rebecca Miles PhD would result in a manuscript being submitted for publication in a high impact Earth Science journal (e.g. Bulletin of Volcanology). Preview of PAS-dataset https://doi.org/10.23729/8fe03af4-9749-4183-be2f-1fa3d2872785

2021