Nd and Sr isotope compositions, REE concentrations and Al/Ca ratios of different phases of surface sediments in the South Pacific ...

• Main Authors: Molina-Kescher, Mario, Frank, Martin, Hathorne, Ed C
• Format: Article in Journal/Newspaper
• Language: English
• Published: PANGAEA 2014
• Subjects: Planktonic foraminifera
• Online Access: https://dx.doi.org/10.1594/pangaea.835638; https://doi.pangaea.de/10.1594/PANGAEA.835638

The radiogenic isotope composition of neodymium (Nd) and strontium (Sr) are useful tools to investigate present and past oceanic circulation or input of terrigenous material. We present Nd and Sr isotope compositions extracted from different sedimentary phases, including early diagenetic Fe-Mn coatings, "unclean" foraminiferal shells, fossil fish teeth, and detritus of marine surface sediments (core-tops) covering the entire midlatitude South Pacific. Comparison of detrital Nd isotope compositions to deep water values from the same locations suggests that "boundary exchange" has little influence on the Nd isotope composition of western South Pacific seawater. Concentrations of Rare Earth Elements (REE) and Al/Ca ratios of "unclean" planktonic foraminifera suggest that this phase is a reliable recorder of seawater Nd isotope composition. The signatures obtained from fish teeth and "nondecarbonated" leachates of bulk sediment Fe-Mn oxyhydroxide coatings also agree with "unclean" foraminifera. Direct comparison ... : Supplement to: Molina-Kescher, Mario; Frank, Martin; Hathorne, Ed C (2014): Nd and Sr isotope compositions of different phases of surface sediments in the South Pacific: Extraction of seawater signatures, boundary exchange, and detrital/dust provenance. Geochemistry, Geophysics, Geosystems ...