New Re-Os Geochronological Data from the Upper Doushantuo Formation: Age Constraint on the Shuram Excursion and Implication for the Ediacaran Fluctuated Continental Weathering
文献类型：期刊论文
| 作者 | Tan, Zhaozhao1,2,4; Luo, Jianlan2,4; Xu, Xuesheng2,4; Jia, Wanglu1; Li, Jie3 ; Chen, Liran2,4
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| 刊名 | ACS OMEGA
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| 出版日期 | 2024-12-03 |
| 卷号 | 9期号:50页码:49121-49131 |
| ISSN号 | 2470-1343 |
| DOI | 10.1021/acsomega.4c05072 |
| 英文摘要 | The largest negative carbon-isotope excursion in geological history has been reported by several studies of the upper Doushantuo Formation of South China, which has been correlated to the middle Ediacaran-Shuram excursion (SE). Due to a scarcity of radiometric age constraints on the excursion in South China, however, global correlations and comparisons of this event remain a debate. Here, we present Re-Os and carbon isotope data on organic-rich sediments obtained from a drill-core sample in the Chengkou area, the northeastern margin of the Yangtze Platform, and South China. The Re-Os geochronology yields a depositional age of 568 +/- 15 Ma (Model 3, MSWD = 1.9, n = 13; 2 sigma), indicating a middle-late Ediacaran age for the upper Doushantuo Formation. This is supported by a negative delta C-13(carb) excursion, which can be reliably correlated to the SE sequences. This age is consistent with the Re-Os radioisotopic dates bracketing the Shuram peaks in Northwest Canada and Oman. A compilation of Os-187/Os-188 and Sr-87/Sr-86 isotope ratios as well as the contents of redox-sensitive elements (RSE) from organic-rich sediments deposited between 635 and 540 Ma shows that the radiogenic Os-187/Os-188 ratios (>1.0) associated with enhanced oxidative weathering occurred at ca. 635, 580, and 560 Ma. As a result, accelerated influxes of nutrients stimulated primary productivity, promoting organic carbon burial and leading to ocean oxygenation. Additionally, elevated continental weathering could have delivered high fluxes of oxidants (e.g., sulfates) to oceans, resulting in transient ocean oxygenation. Corresponding to elevated radiogenic Os and Sr isotope ratios, the significant RSE enrichments at these three times indicate the presence of large marine RSE reservoirs and an oxygenated ocean. Therefore, the Re-Os age and initial Os isotope composition of organic-rich shale can be a sensitive tool for constraining the time interval of enhanced continental weathering and resulting pulses of ocean oxygenation during the Neoproterozoic era. |
| WOS研究方向 | Chemistry |
| 语种 | 英语 |
| WOS记录号 | WOS:001369805200001 |
| 源URL | [http://ir.gig.ac.cn/handle/344008/81944]  |
| 专题 | 有机地球化学国家重点实验室 |
| 通讯作者 | Tan, Zhaozhao |
| 作者单位 | 1.Chinese Acad Sci, Guangzhou Inst Geochem, State Key Lab Organ Geochem, Guangzhou 510640, Peoples R China 2.Hunan Prov Key Lab Geochem Proc & Resource Environ, Changsha 410014, Hunan, Peoples R China 3.Chinese Acad Sci, Guangzhou Inst Geochem, State Key Lab Isotope Geochem, Guangzhou 510640, Peoples R China 4.Geophys & Geochem Survey Inst Hunan Prov, Changsha 410014, Hunan, Peoples R China |
| 推荐引用方式 GB/T 7714 | Tan, Zhaozhao,Luo, Jianlan,Xu, Xuesheng,et al. New Re-Os Geochronological Data from the Upper Doushantuo Formation: Age Constraint on the Shuram Excursion and Implication for the Ediacaran Fluctuated Continental Weathering[J]. ACS OMEGA,2024,9(50):49121-49131. |
| APA | Tan, Zhaozhao,Luo, Jianlan,Xu, Xuesheng,Jia, Wanglu,Li, Jie,&Chen, Liran.(2024).New Re-Os Geochronological Data from the Upper Doushantuo Formation: Age Constraint on the Shuram Excursion and Implication for the Ediacaran Fluctuated Continental Weathering.ACS OMEGA,9(50),49121-49131. |
| MLA | Tan, Zhaozhao,et al."New Re-Os Geochronological Data from the Upper Doushantuo Formation: Age Constraint on the Shuram Excursion and Implication for the Ediacaran Fluctuated Continental Weathering".ACS OMEGA 9.50(2024):49121-49131. |
入库方式： OAI收割
来源：广州地球化学研究所
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