CAT-scan analysis in scientific drilling: effective routine data acquisition and processing of whole cores, split cores and u-channels

CAT-scan analysis of sediment cores provides a rapid, high-resolution and non destructive method to visualise sedimentary structures, coring-induced artefacts, as well as to derive a continuous downcore CT number profile primarily associated with changes in bulk density. Here, we will briefly overview how we now routinely use CAT-scan analysis for paleoenvironmental and sedimentological purposes. We will present some advances in data processing, as well as a few case studies from lacustrine and marine sedimentary sequences measured using either whole cores, split cores and u-channels in order to highlight the advantages and complementarity of CAT-Scan measurements with other continuous downcore high-resolution physical or magnetic measurements. We will also illustrate how effective data acquisition and processing have now enabled the use of CAT-scan for the continuous interpretation of long drilled sequences from IODP (Exp. 341 – Gulf of Alaska) and ICDP (PASADO – Laguna Potrok Aike, Southern Patagonia) previously hampered by the large number of core sections and derived images.