Early diagenetic imprints and U-Th isotope systematics of fossil land snail shells from the Chinese Loess Plateau
文献类型：期刊论文
| 作者 | Li, Tao3,4,5,6; Chen, Tianyu4,5; Robinson, Laura F.3; Wang, Maoyu4,5; Li, Gaojun4,5; Liu, Yuanyuan4,5; Knowles, Timothy D. J.1,2 |
| 刊名 | QUATERNARY GEOCHRONOLOGY
 |
| 出版日期 | 2023-02-01 |
| 卷号 | 74页码:13 |
| ISSN号 | 1871-1014 |
| 关键词 | Cathaica sp. Chinese Loess Plateau Trace elements Diagenetic alteration Uranium-series dating Raman spectroscopy LA-MC-ICPMS Solution MC-ICPMS |
| DOI | 10.1016/j.quageo.2022.101417 |
| 通讯作者 | Li, Tao(taoli@nigpas.ac.cn) ; Chen, Tianyu(tianyuchen@nju.edu.cn) |
| 英文摘要 | The loess-paleosol sequence on the Chinese Loess Plateau provides a unique archive that records climate change in East Asia in the Quaternary, yet absolute dating of the loess deposits is challenging due to the lack of directly datable materials. Fossil land snail shells, which are made from aragonite, are widely preserved in the loess deposits and have long been used to reconstruct past environmental changes. U-series dating of fossil land snail shells has the potential to provide a route for absolute dating of the loess deposits but remains largely unexplored. In this study, we present the first systematic investigation on the U-series isotope geochemistry as well as the early diagenetic imprints of fossil land snail shells (Cathaica sp.) from the Mangshan loess-paleosol sequence in Henan province, central China. Several geochemical techniques, including Raman microscopy, SEM, LA-ICPMS, LA-MC-ICPMS, solution-MC-ICPMS, and AMS C-14 dating, were employed to investigate the mineralogy, chemical and isotopic compositions of both modern and fossil snail shells to micrometer level. Our results show that the fossil Cathaica sp. shells are overall characterized by a higher degree of porosity and elevated contents of organic matter compared to live-collected shells of the same species. The layers with higher porosity and organic matter content in the fossil Cathaica sp. shell are also found to be enriched in Na, Mg, Mn, Ba, and U, indicating diffusion and adsorption of these elements by specific surface binding sites of either aragonitic lattice or organic compounds of the fossil shell. Combining in-situ measurements using LA-MC-ICPMS with solution U-series determination, we further demonstrate that fossil Cathaica sp. shell is relatively homogeneous regrading both [U-234/U-238] and [Th-230/U-238] values although the distribution of U in the fossil shell is sample-specific. The comparison of different dating results suggests that the calculated apparent closed system U-Th ages are all systematically younger (similar to 6000 to 13,000 years) than the corresponding shell C-14 ages and quartz SAR (single-aliquot regenerative-dose) ages from the Mangshan section. We suggest that the underestimation of U-Th ages of fossil Cathaica sp. shells is very likely caused by diagenetic uptake of U that started immediately after the burial of the shell and effectively ceased when the fossil shell was isolated from the pore waters due to persistent deposition of eolian dust at the Mangshan section. Our work on both modern and fossil Cathaica sp. shells thus provides detailed morphological and geochemical characterization for the diagenetic alteration of fossil snail shells and suggests that U-series dating of fossil land snail shells may provide age constraints for dust deposits in the semi-arid region although the timing of early diagenetic U-uptake by the fossil shells need to be better quantified for reliable age determination. |
| WOS关键词 | YELLOW-RIVER ; MONSOON PRECIPITATION ; PALEOSOL SEQUENCE ; ORGANIC-MATTER ; EAST-ASIA ; URANIUM ; CALCITE ; RADIOCARBON ; ARAGONITE ; MARINE |
| 资助项目 | Strategic Priority Research Program of Chinese Academy of Sciences[XDB40010200] ; National Natural Science Foundation of China[41991325] ; National Natural Science Foundation of China[42002198] ; National Natural Science Foundation of China[41711530222] ; Royal Society Newton Mobility Grant ; China Scholarship Council ; Nanjing University |
| WOS研究方向 | Physical Geography ; Geology |
| 语种 | 英语 |
| 出版者 | ELSEVIER SCI LTD |
| WOS记录号 | WOS:000897148300003 |
| 资助机构 | Strategic Priority Research Program of Chinese Academy of Sciences ; National Natural Science Foundation of China ; Royal Society Newton Mobility Grant ; China Scholarship Council ; Nanjing University |
| 源URL | [http://ir.nigpas.ac.cn/handle/332004/41564]  |
| 专题 | 中国科学院南京地质古生物研究所 |
| 通讯作者 | Li, Tao; Chen, Tianyu |
| 作者单位 | 1.Univ Bristol, Sch Arts, Bristol BS8 1RJ, England 2.Univ Bristol, Sch Chem, Bristol Radiocarbon Accelerator Mass Spectrometry, Bristol BS8 1RJ, England 3.Univ Bristol, Sch Earth Sci, Bristol BS8 1RJ, England 4.Nanjing Univ, Frontiers Sci Ctr Crit Earth Mat Cycling, Nanjing 210023, Peoples R China 5.Nanjing Univ, Sch Earth Sci & Engn, Nanjing 210023, Peoples R China 6.Chinese Acad Sci, Nanjing Inst Geol & Palaeontol, State Key Lab Palaeobiol & Stratig, Nanjing 210008, Peoples R China |
| 推荐引用方式 GB/T 7714 | Li, Tao,Chen, Tianyu,Robinson, Laura F.,et al. Early diagenetic imprints and U-Th isotope systematics of fossil land snail shells from the Chinese Loess Plateau[J]. QUATERNARY GEOCHRONOLOGY,2023,74:13. |
| APA | Li, Tao.,Chen, Tianyu.,Robinson, Laura F..,Wang, Maoyu.,Li, Gaojun.,...&Knowles, Timothy D. J..(2023).Early diagenetic imprints and U-Th isotope systematics of fossil land snail shells from the Chinese Loess Plateau.QUATERNARY GEOCHRONOLOGY,74,13. |
| MLA | Li, Tao,et al."Early diagenetic imprints and U-Th isotope systematics of fossil land snail shells from the Chinese Loess Plateau".QUATERNARY GEOCHRONOLOGY 74(2023):13. |
入库方式： OAI收割
来源：南京地质古生物研究所
浏览0
下载0
收藏0
其他版本
除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。