DOI: 10.1016/j.palaeo.2016.09.007
论文题名: Rare earth elements in conodont apatite: Seawater or pore-water signatures?
作者: Trotter J.A. ; Barnes C.R. ; McCracken A.D.
刊名: Palaeogeography, Palaeoclimatology, Palaeoecology
ISSN: 0031-0182
出版年: 2016
卷: 462 起始页码: 92
结束页码: 100
语种: 英语
英文关键词: Bioapatite
; Laser ICPMS
; Matrix effects
; Palaeoseawater
; REE partitioning
英文摘要: Rare earth element (REE) compositions of Lower Palaeozoic conodont microfossils from different sites in Laurentia are presented and compared to modern pore-water REE compositions reported in the literature. These data are modelled to account for matrix-induced fractionation of REEs during uptake by apatite. The apatite-water partition co-efficients (Kd) for adsorption of REEs are applied to a range of modern pore-water compositions (i.e. Pore-waterN × Kd), the resultant data being similar to Palaeozoic conodont apatite compositions. Similar resemblances to modern pore-water REE compositions are shown by palaeofluids derived from conodonts using the inverse relationship in REE adsorption kinetics (i.e. Bioapatite/Kd), with rare low concentration samples yielding HREE-enriched patterns. These results clearly show the importance of matrix effects and hence the post-mortem physico-chemical processes by which elemental uptake occurs in fossil biogenic minerals, which are crucial to consider when interpreting geochemical signatures. Furthermore, the similarities between apatite REE compositions of conodonts and those derived from modern pore-waters challenge prior hypotheses of seawater REE evolution inferred directly from conodont apatite, and question the reliability of conodont apatite as archives of seawater REE chemistry. These outcomes likely have broader implications for fossil bioapatites in general given the physico-chemical processes occurring within marine sediments and the inherent behaviour of apatite-REE systematics. © 2016 Elsevier B.V. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/68207
Appears in Collections: 过去全球变化的重建
There are no files associated with this item.
作者单位: School of Earth and Environment, The University of Western Australia, Perth, WA, Australia; School of Earth and Ocean Sciences, University of Victoria, Victoria, BC, Canada; Geological Survey of Canada, Calgary, AB, Canada
Recommended Citation:
Trotter J.A.,Barnes C.R.,McCracken A.D.. Rare earth elements in conodont apatite: Seawater or pore-water signatures?[J]. Palaeogeography, Palaeoclimatology, Palaeoecology,2016-01-01,462