2001; Rasmussen et al. 2007) and meltwater plumes (e.g., Lekens et al. 2005;
Rasmussen et al. 2007; Łącka et al. 2014) significantly influence the MS. Therefore,
MS has been used for lithostratigraphic correlations (e.g., Antoniades et al. 2011;
Ojala et al. 2014), reconstructions of sedimentation patterns (e.g., Helmke et al.
2005; Lekens et al. 2006; Jessen et al. 2010), reconstructions of ice sheet dynamics
(Antoniades et al. 2011), or recently to trace palaeo-methane emissions off western
Svalbard (Johnson et al. 2014).
2.6 X-Ray Fluorescence (XRF)
X-ray fluorescence core scanning (XRF) was first developed at the Netherlands
Institute for Sea Research (NIOZ) in 1988 (Jansen et al. 1998). It is a nondestructive, nearly continuous, and relatively fast analytical method of the down-core
variability in the elemental composition of sediments from aluminium to uranium
(Richter et al. 2006). It is based on the principle that X-rays collide with matter,
which leads to the generation of secondary radiation, i.e., fluorescence. This makes
it possible to determine the qualitative and quantitative element compositions of
solids, liquids and powders.
XRF can provide high-resolution palaeoenvironmental information in a variety
of sedimentary settings. It has been applied to broad palaeoceanographic reconstructions, such as initial correlations between cores, preliminary stratigraphic
interpretations of sedimentary sequences (e.g., Norris and Röhl 1999; Pälike et al.
2001), investigations of terrigenous input patterns (e.g., Croudace et al. 2006) and
the provenance of terrigenous material (e.g., Haug et al. 2001; Lamy et al. 2004),
tracing early diagenetic processes (Funk et al. 2004), spectral analyses of Milankovitch orbital cycles and sedimentation rate analysis (Peterson et al. 2000; Pälike
et al. 2001, 2008). In the Arctic Ocean, it has been used to reconstruct the Palaeogene (Spofforth et al. 2008; Hanslik et al. 2013) and Late Quaternary (Polyak et al.
2009) stratigraphy and the glacial-interglacial variability of manganese content
(Löwemark et al. 2008).
The interpretation of XRF results should be based on elemental ratios instead of
single elements (e.g., Weltje and Tjallingii 2008). The most commonly used ratios
for palaeoclimate reconstructions in the Arctic region are iron/calcium (Fe/Ca),
titanium/calcium (Ti/Ca), titanium/aluminium (Ti/Al), iron/potassium (Fe/K) and
aluminium/silicon (Al/Si) (Govin et al. 2012; see Table 1). Fe and Ti vary with the
terrigenous fraction of the sediment because they are related to the siliciclastic
components of the sediment (e.g., Arz et al. 1998; Jansen et al. 1998). In contrast,
the coarse sediment fractions are enriched in Ti (e.g., Schütz and Rahn 1982; Shiller
1982), while Al and Si are mostly associated with fine-particle clay minerals
(Biscaye 1965). Hence, the Si/Fe ratio is regarded as a proxy for the supply of
sediments from glacial meltwater (Erbs-Hansen et al. 2013). Ca often represents the
carbonate content of the sediment, the biological productivity of the surface water,
the rate of dissolution during its journey through the water column and on the
New Methods in the Reconstruction of Arctic Marine …
137
Rasmussen et al. 2007; Łącka et al. 2014) significantly influence the MS. Therefore,
MS has been used for lithostratigraphic correlations (e.g., Antoniades et al. 2011;
Ojala et al. 2014), reconstructions of sedimentation patterns (e.g., Helmke et al.
2005; Lekens et al. 2006; Jessen et al. 2010), reconstructions of ice sheet dynamics
(Antoniades et al. 2011), or recently to trace palaeo-methane emissions off western
Svalbard (Johnson et al. 2014).
2.6 X-Ray Fluorescence (XRF)
X-ray fluorescence core scanning (XRF) was first developed at the Netherlands
Institute for Sea Research (NIOZ) in 1988 (Jansen et al. 1998). It is a nondestructive, nearly continuous, and relatively fast analytical method of the down-core
variability in the elemental composition of sediments from aluminium to uranium
(Richter et al. 2006). It is based on the principle that X-rays collide with matter,
which leads to the generation of secondary radiation, i.e., fluorescence. This makes
it possible to determine the qualitative and quantitative element compositions of
solids, liquids and powders.
XRF can provide high-resolution palaeoenvironmental information in a variety
of sedimentary settings. It has been applied to broad palaeoceanographic reconstructions, such as initial correlations between cores, preliminary stratigraphic
interpretations of sedimentary sequences (e.g., Norris and Röhl 1999; Pälike et al.
2001), investigations of terrigenous input patterns (e.g., Croudace et al. 2006) and
the provenance of terrigenous material (e.g., Haug et al. 2001; Lamy et al. 2004),
tracing early diagenetic processes (Funk et al. 2004), spectral analyses of Milankovitch orbital cycles and sedimentation rate analysis (Peterson et al. 2000; Pälike
et al. 2001, 2008). In the Arctic Ocean, it has been used to reconstruct the Palaeogene (Spofforth et al. 2008; Hanslik et al. 2013) and Late Quaternary (Polyak et al.
2009) stratigraphy and the glacial-interglacial variability of manganese content
(Löwemark et al. 2008).
The interpretation of XRF results should be based on elemental ratios instead of
single elements (e.g., Weltje and Tjallingii 2008). The most commonly used ratios
for palaeoclimate reconstructions in the Arctic region are iron/calcium (Fe/Ca),
titanium/calcium (Ti/Ca), titanium/aluminium (Ti/Al), iron/potassium (Fe/K) and
aluminium/silicon (Al/Si) (Govin et al. 2012; see Table 1). Fe and Ti vary with the
terrigenous fraction of the sediment because they are related to the siliciclastic
components of the sediment (e.g., Arz et al. 1998; Jansen et al. 1998). In contrast,
the coarse sediment fractions are enriched in Ti (e.g., Schütz and Rahn 1982; Shiller
1982), while Al and Si are mostly associated with fine-particle clay minerals
(Biscaye 1965). Hence, the Si/Fe ratio is regarded as a proxy for the supply of
sediments from glacial meltwater (Erbs-Hansen et al. 2013). Ca often represents the
carbonate content of the sediment, the biological productivity of the surface water,
the rate of dissolution during its journey through the water column and on the
New Methods in the Reconstruction of Arctic Marine …
137