Subducted serpentinite contributes to the formation of arc lavas with heavy Mo isotopic compositions
文献类型：期刊论文
| 作者 | Dai, Fu-Qiang1,4; Chen, Yi-Xiang2,3; Chen, Ren-Xu2,3; Zhao, Zi-Fu2,3; Li, Jie3 ; Wang, Yu4; Zhang, Lifei4
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| 刊名 | GEOCHIMICA ET COSMOCHIMICA ACTA
 |
| 出版日期 | 2024-03-15 |
| 卷号 | 369页码:62-70 |
| 关键词 | Mo isotopes Serpentinite Island arc magmatism Fluid Subduction zone |
| ISSN号 | 0016-7037 |
| DOI | 10.1016/j.gca.2024.01.033 |
| 英文摘要 | The petrogenesis of basaltic arc lavas with heavy Mo isotopic compositions is controversial. Given that oceanic crust preferentially loses isotopically heavy Mo during subduction at forearc depth and the remaining Mo is isotopically light and locked in rutile, fluids derived from such crust at subarc depth cannot account for the heavy Mo isotopic compositions of basaltic arc lavas. Serpentinites can contain substantial Mo and volatiles and are a potential source of isotopically heavy Mo in basaltic arc lavas. However, the Mo isotopic composition of serpentinites and the Mo isotope behavior during serpentinite dehydration are poorly constrained. Here, we present Mo contents and isotope data for serpentinites from the South Sandwich Trench-Fracture Zone intersection, and deserpentinized peridotites and high-pressure meta-serpentinite veins from the western-central Alps and Betic Cordillera, Spain. Most of these samples have heavy Mo isotopic compositions (delta 98/95MoNIST 3134, ranging from -0.26 %o to 1.84 %o) with low Ce/Mo (0.10-23.98) and Ce/Pb (0.17-3.59) ratios, which are distinct from the compositions of eclogite-facies metabasalts and metapelites. In addition, no systematic variations in Mo contents and Mo isotopic compositions occur for the studied samples, indicating limited Mo isotope fractionation during serpentinite dehydration. The above results suggest that serpentinites and their derived fluids at subarc depths can serve as the main isotopically heavy Mo sources for basaltic arc lavas. The Mo isotope data with Ce/Mo and Ce/Pb systematics suggest that serpentinite-derived fluids or melting of serpentinite diapirs at subarc depths can explain the heavy Mo isotopic compositions of basaltic arc lavas. Furthermore, recycled oceanic slab (oceanic crust + serpentinized mantle) would has limited influence on the Mo systematics of the mantle, which explains why the mantle has maintained a nearly constant Mo isotopic composition since 3.5 Ga. |
| WOS研究方向 | Geochemistry & Geophysics |
| 语种 | 英语 |
| WOS记录号 | WOS:001182145200001 |
| 源URL | [http://ir.gig.ac.cn/handle/344008/77285]  |
| 专题 | 同位素地球化学国家重点实验室 |
| 通讯作者 | Dai, Fu-Qiang |
| 作者单位 | 1.Hohai Univ, Inst Marine Geol, Coll Oceanog, Nanjing 210098, Peoples R China 2.Univ Sci & Technol China, Sch Earth & Space Sci, CAS Key Lab Crust Mantle Mat & Environm, Hefei 230026, Peoples R China 3.Univ Sci & Technol China, CAS Ctr Excellence Comparat Planetol, Hefei 230026, Peoples R China 4.Chinese Acad Sci, Guangzhou Inst Geochem, State Key Lab Isotope Geochem, Guangzhou 510640, Peoples R China |
| 推荐引用方式 GB/T 7714 | Dai, Fu-Qiang,Chen, Yi-Xiang,Chen, Ren-Xu,et al. Subducted serpentinite contributes to the formation of arc lavas with heavy Mo isotopic compositions[J]. GEOCHIMICA ET COSMOCHIMICA ACTA,2024,369:62-70. |
| APA | Dai, Fu-Qiang.,Chen, Yi-Xiang.,Chen, Ren-Xu.,Zhao, Zi-Fu.,Li, Jie.,...&Zhang, Lifei.(2024).Subducted serpentinite contributes to the formation of arc lavas with heavy Mo isotopic compositions.GEOCHIMICA ET COSMOCHIMICA ACTA,369,62-70. |
| MLA | Dai, Fu-Qiang,et al."Subducted serpentinite contributes to the formation of arc lavas with heavy Mo isotopic compositions".GEOCHIMICA ET COSMOCHIMICA ACTA 369(2024):62-70. |
入库方式： OAI收割
来源：广州地球化学研究所
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