A comparison of mm scale resolution techniques for element analysis in sediment cores


Contact
Dorothee.Dick [ at ] awi.de

Abstract

Laminated sediment records from the oxygen minimum zone in the Arabian Sea offer unique ultrahighresolution archives for deciphering climate variability in the Arabian Sea region. Although numerous analytical techniques are available it has become increasingly popular during the past decade to analyze relative variations of sediment cores’ chemical signature by non-destructive X-ray fluorescence (XRF)core scanning. We carefully selected an approximately 5 m long sediment core from the northern Arabian Sea (GeoB12309-5: 24:52.3°N; 62:59.9°E, 956 m water depth) for a detailed, comparative study of high-resolution techniques, namely non-destructive XRF core scanning (0.8 mm resolution)and ICP-MS/OES analysis on carefully selected, discrete samples (1 mm resolution). The aim of our study was to more precisely define suitable chemical elements that can be accurately analyzed and to determine which elemental ratios can be interpretated down to sub-millimeter-scale resolutions. Applying the Student’s t-test our results show significantly correlating (1% significance level) elemental patterns for all S, Ca, Fe, Zr, Rb, and Sr, as well as the K/Ca, Fe/Ti and Ti/Al ratios that are all related to distinct lithological changes. After careful consideration of all errors for the ICP analysis we further provide respective factors of XRF Core Scanner software error’s underestimation by applying c2-tests, which is especially relevant for elements with high count rates. As demonstrated by these new, ultrahigh resolution data core scanning has major advantages (high-speed, low costs, few sample preparation steps) and represents an increasingly required alternative over the time consuming, expensive, elaborative, and destructive wet chemical analyses (e.g., by ICP-MS/OES after acid digestions), and meanwhile also provides high-quality data in unprecedented resolution.



Item Type
Article
Authors
Divisions
Primary Division
Programs
Primary Topic
Peer revision
Scopus/ISI peer-reviewed
Publication Status
Published
Eprint ID
30965
DOI 10.1039/c2ja30148b

Cite as
Wilhelms-Dick, D. , Westerhold, T. , Röhl, U. , Wilhelms, F. , Vogt, C. , Hanebuth, T. J. J. , Römmermann, H. , Kriews, M. and Kasten, S. (2012): A comparison of mm scale resolution techniques for element analysis in sediment cores , Journal of Analytical Atomic Spectrometry, 27 , pp. 1574-1584 . doi: 10.1039/c2ja30148b


Share


Citation

Research Platforms
N/A

Campaigns


Actions
Edit Item Edit Item