Itrax-2-Austria: Introducing and advancing XRF-core scanning

Applicant (AP) - Dr. Jyh-Jaan Steven Huang, Austrian Core Facility, Institute of Geology, University of Innsbruck. Austrian Co-Applicant (Co-AP) - Univ.-Prof. Dr. Michael Strasser, Institute of Geology, University of Innsbruck. Public relations abstract: Understanding the intricate interaction between humans and its surrounding environment is a fundamental and social-relevant goal of modern Earth and Environmental Sciences to illuminate the sustainable future of mankind. Lacustrine and marine sediments often contain long records of Earth processes such as climate changes, local and regional events and anthropogenic imprints. However, the abrupt and rapid signals of human-environmental interactions due to natural (e.g. storms, floods, earthquakes or tsunamis) or anthropogenic (e.g. land use changes or pollutions) events are extraordinarily challenging to be deciphered from natural archives at societally-relevant timescales. Motivated by the mission to analyze natural archives sampled by scientific drilling and coring for investigating past records as well as studying rates and states of Earth-system processes to improve our understanding of complex interactions between tectonic, climatic and anthropogenic impacts. This project, for the first time in Austria, will introduce advanced X-ray Fluorescence core scanning (XRF-CS) data analyses and interpretations to the Austrian scientific community and develop new methodological approaches for advancing research applications worldwide. The fast and non-destructive XRF-CS technique can be used to measure element abundances from Al to U directly at the surface of samples. Fascinating ultra-high resolution down-core elemental variations then are produced as indicators (or so called proxies) for past environmental and process changes down to annual and even sub-annual timescales. Over the last decade, XRF-CS technique has revolutionized element proxy based paleo-researches conducted at the leading international research facilities and now has just recently begun to be operated at the Austrian Core Facility of the University of Innsbruck. Yet, long-standing methodological challenges, including (1) automated quality assurance and quality control (QA/QC); (2) quantitative calibration of element concentrations (3) and dealing with big datasets as proxy-based interpretations, remain to be addressed towards harvesting the full potential of the XRF-CS technique. The Itrax-2-Austria project therefore aims at evaluating and applying new mathematical, calibrated and statistical approaches on experimental and natural datasets available through collaborations with ongoing research projects by cooperation partners of the Austrian Core Facility. With a special focus on Lake Millstättersee (Austrian Eastern Alps) as a well-suited case study site to test and further develop the new approach, annually-laminated sedimentary sequences will be analyzed to study past extreme events archived in the geological records. This is expected to produce fascinating records of geochemically fingerprinted event deposits allowing for advanced process-based interpretation of long-term records unravelling frequency and cause-and-effect relationships between natural hazards, environmental perturbation and resilience and related human-environmental interconnections.

Understanding the intricate interaction between humans and its surrounding environment is a fundamental and social-relevant goal of modern Earth and Environmental Sciences to illuminate the sustainable future of mankind. Lacustrine and marine sediments often contain long records of Earth processes such as climate changes, local and regional events, and anthropogenic imprints. However, the abrupt and rapid signals of human-environmental interactions due to natural (e.g. storms, floods, earthquakes, or tsunamis) or anthropogenic (e.g. land-use changes or pollutions) events are extraordinarily challenging to be deciphered from natural archives at societally-relevant timescales. Motivated by the mission to analyze natural archives sampled by scientific drilling and coring for investigating past records as well as studying rates and states of Earth-system processes to improve our understanding of complex interactions between tectonic, climatic, and anthropogenic impacts. This project, for the first time in Austria, introduced advanced X-ray Fluorescence core scanning (XRF-CS) data analyses and interpretations to the Austrian scientific community and develop new methodological approaches for advancing research applications worldwide. The fast and non-destructive XRF-CS technique can be used to measure element abundances from Al to U directly at the surface of samples. Fascinating ultra-high-resolution down-core elemental variations then are produced as indicators (or so-called "proxies") for past environmental and process changes down to annual and even sub-annual timescales. Yet, long-standing methodological challenges, including (1) automated quality assurance and quality control (QA/QC); (2) quantitative calibration of element concentrations (3) and dealing with big datasets as proxy-based interpretations, remain to be addressed towards harvesting the full potential of the XRF-CS technique. The Itrax-2-Austria project successfully developed an automatic workflow, including (1) reliable QA/QC by depth-dependence local similarity evaluation, (2) calibrating the organic dilution problem by centered-log ratio transformation, and (3) usages of robust multivariate statistical methods, to efficiently process the XRF-CS data and to reduce human bias. Particular focus was devoted to annually-varved lake Millstättersee (Austria), which has 700 years of historical records documenting floods, earthquakes, and human occupation. 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. Moreover, such a toolbox can be used to explore any XRF-CS datasets for automatic data processing and discrimination. This outcome of the Itrax-2-Austria project can thus shed new light on the scientific challenges by the cooperation partners of the Austrian Core Facility and the international XRF-CS community.