[M-IS03] Developments and applications of XRF-core scanning techniques in natural archives

[MIS03-P05] A comprehensive 3-steps workflow of evaluation, transformation, and recognition towards automatic XRF-core scanning data processing

*Jyh-Jaan Steven Huang¹, Arata Kioka², Christoph Daxer¹, Jasper Moernaut¹, Michael Strasser¹ (1.Institute of Geology, University of Innsbruck, Austria., 2.Department of Earth Resources Engineering, Kyushu University, Japan.)

X-ray fluorescence core scanning (XRF-CS) technique provides fast, high resolution, and non-destructive analyses to assess down-core elemental variations as indicators for past environmental and process changes down to annual and even sub-annual resolution. Although it has revolutionized elemental proxy-based paleo-researches over the last decade, three long-standing challenges, including (1) reliable quality assurance and quality control (QA/QC); (2) calibration of the matrix and closed-sum effect; (3) dealing with big datasets as proxy-based interpretations, remain to be addressed towards harvesting the full potential of the XRF-CS technique. Here, an automatic workflow, including (1) reliable QA/QC by depth-dependence local similarity evaluation, (2) calibrating the matrix and closed-sum problem by centered-log ratio transformation, and (3) usages of robust multivariate statistical methods, is provided to efficiently process the XRF-CS data and to reduce human bias. Particular focus is devoted to annually-varved lake Millstättersee (Austria), which has 700 years historical records documenting floods, earthquakes, and human occupation, as well as fascinating sedimentary records. By testing and applying our approach, the geochemical fingerprints of event deposits can be revealed and calibrated with historically known events. The causes-and-consequences of environmental perturbations can therefore be discussed.