Application of laser-induced breakdown spectroscopy to Arctic sediments in the Chukchi Sea

Abstract

Physical and geochemical investigations coupled with laser-induced breakdown spectroscopy (LIBS) were performed on three surface sediment cores (ARA02B/01A, ARA02B/02, and ARA02B/03A) recovered from the western Arctic Ocean (Chukchi Sea) during the IBRV ARAON 2011 expedition. The LIBS technique was applied to conduct elemental analysis of the Arctic sediments and compare the results to those obtained using an X-ray fluorescence (XRF) core scanner and inductively coupled plasma (ICP) system. The LIBS technique showed an elemental composition similar to that using XRF and ICP in each sediment core. Qualitative and semi-quantitative LIBS analyses provide distinguishable patterns between sediment cores, similar to those observed in the ICP analysis. In particular, the elemental pattern of LIBS responded to the color change of the sediment cores. Dark brown layers in the upper parts of the cores were indicated by the color indices and showed elevated Mn/Al ratios, suggesting the influence of regional variation in terrestrial input since the deglacial period. In this study, grain size distribution and contents of detrital dolomite and organic carbon as well as elemental composition (LIBS) were considered to determine sediment provenance and sedimentation environments during the Holocene. Furthermore, the present study showed that the LIBS technique may be used as an applicable method to unravel regional variations in sedimentary composition in the Arctic Ocean.