High-resolution analysis of trace elements in crustose coralline algae from the North Atlantic and North Pacific by laser ablation ICP-MS

Autor: Barbara E. Kunz, Walter H. Adey, Andreas Kronz, Steffen Hetzinger, Dorrit E. Jacob, Thomas Zack, Jochen Halfar, G. Gamboa, P. A. Lebednik, Robert S. Steneck
Rok vydání: 2011
Předmět:
Zdroj: Palaeogeography, Palaeoclimatology, Palaeoecology. 302:81-94
ISSN: 0031-0182
DOI: 10.1016/j.palaeo.2010.06.004
Popis: We have investigated the trace elemental composition in the skeleta of two specimens of attached-living coralline algae of the species Clathromorphum compactum from the North Atlantic (Newfoundland) and Clathromorphum nereostratum from the North Pacific/Bering Sea region (Amchitka Island, Aleutians). Samples were analyzed using Laser Ablation-Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) yielding for the first time continuous individual trace elemental records of up to 69 years in length. The resulting algal Mg/Ca, Sr/Ca, U/Ca, and Ba/Ca ratios are reproducible within individual sample specimens. Algal Mg/Ca ratios were additionally validated by electron microprobe analyses (Amchitka sample). Algal Sr/ Ca, U/Ca, and Ba/Ca ratios were compared to algal Mg/Ca ratios, which previously have been shown to reliably record sea surface temperature (SST). Ratios of Sr/Ca from both Clathromorphum species show a strong positive correlation to temperature-dependent Mg/Ca ratios, implying that seawater temperature plays an important role in the incorporation of Sr into algal calcite. Linear Sr/Ca-SST regressions have provided positive, but weaker relationships as compared to Mg/Ca-SST relationships. Both, algal Mg/Ca and Sr/Ca display clear seasonal cycles. Inverse correlations were found between algal Mg/Ca and U/Ca, Ba/Ca, and correlations to SST are weaker than between Mg/Ca, Sr/Ca and SST. This suggests that the incorporation of U and Ba is influenced by other factors aside from temperature
Databáze: OpenAIRE