Sulfur Isotope Evidence for a Geochemical Zonation of the Samoan Mantle Plume
Sulfur Isotope Evidence for a Geochemical Zonation of the Samoan Mantle Plume
复制标题
萨摩亚地幔柱地球化学分带的硫同位素证据
DOI：
10.1029/2021gc009816
复制
发表时间：
2021
期刊：
影响因子：
--
通讯作者：
Farquhar, James
中科院分区：
文献类型：
--
作者：
Dottin, III, James W.;Labidi, Jabrane;Jackson, Matthew G.;Farquhar, James
萨摩亚火山的玄武岩样本来自所有经典地幔端元的贡献，包括极端 EM II 和高 3He/4He 成分，以及来自 HIMU、EM I 和 DM 成分的稀释成分。在这里，我们提供了从与萨摩亚几座火山（瓦卢卢乌火山、马鲁马鲁火山、马鲁图火山、乌波卢火山、萨瓦伊火山和图图伊拉火山）提取的硫化物的多个硫同位素数据，这些数据对萨摩亚火山的全部地球化学非均质性进行了采样，并在详尽汇编了萨摩亚熔岩的硫同位素数据后，可以评估与萨摩亚熔岩相关的硫同位素组成。萨摩亚热点采样的不同地幔成分。我们观察到不同的 S 浓度 (10–1,000 ppm) 和 δ34S 值（−0.29‰ ± 0.30 至 +4.84‰ ± 0.30, 2σ）。观察到的可变硫浓度可能是由于硫化物偏析和脱气过程造成的。 δ34S 的范围反映了地幔起源和回收成分之间的混合，以及与脱气相关的同位素分馏。大多数样品显示 Δ33S 的不确定度为 Δ33S = 0‰ ± 0.008。这一观察结果的重要例外包括：(a) 乌波卢岛再生玄武岩的负 Δ33S (−0.018±0.008, 2σ)（与稀释的 EMI 成分相关）和 (b) 先前记录的与 Vai 趋势相关的小（但可解析）Δ33S 值（高达 +0.027 ±0.016）（与稀释的 HIMU 相关）组件）。我们在 Δ33S 中观察到的变异性被解释为反映了不同来源的硫和可能的多个地壳原岩的贡献。 Δ36S 与 Δ33S 关系表明所有回收的 S 都是后太古代起源的。
Basalts from the Samoan volcanoes sample contributions from all of the classical mantle endmembers, including extreme EM II and high3He/4He components, as well as dilute contributions from the HIMU, EM I, and DM components. Here, we present multiple sulfur isotope data on sulfide extracted from subaerial and submarine whole rocks (N= 16) associated with several Samoan volcanoes—Vailulu‘u, Malumalu, Malutut, Upolu, Savai‘i, and Tutuila—that sample the full range of geochemical heterogeneity at Samoa and upon exhaustive compilation of S‐isotope data for Samoan lavas, allow for an assessment of the S‐isotope compositions associated with the different mantle components sampled by the Samoan hotspot. We observe variable S concentrations (10–1,000 ppm) and δ34S values (−0.29‰ ± 0.30 to +4.84‰ ± 0.30, 2σ). The observed variable S concentrations are likely due to sulfide segregation and degassing processes. The range in δ34S reflects mixing between the mantle origin and recycled components, and isotope fractionations associated with degassing. The majority of samples reveal Δ33S within uncertainty of Δ33S = 0‰ ± 0.008. Important exceptions to this observation include: (a) a negative Δ33S (−0.018‰ ± 0.008, 2σ) from a rejuvenated basalt on Upolu island (associated with a diluted EM I component) and (b) previously documented small (but resolvable) Δ33S values (up to +0.027 ± 0.016) associated with the Vai Trend (associated with a diluted HIMU component). The variability we observed in Δ33S is interpreted to reflect contributions of sulfur of different origins and likely multiple crustal protoliths. Δ36S versus Δ33S relationships suggest all recycled S is of post‐Archean origin.
登录
查看更多内容
影响因子：
3.5
作者：
Adams, J., V;Spera, F. J.;Jackson, M. G.
通讯作者：
Jackson, M. G.
部分熔融过程中可忽略不计的硫同位素分馏：来自加勒特变换断层玄武岩的证据，对晚单板和玄武岩的影响
影响因子：
5.3
作者：
Jabrane Labidi;P. Cartigny
通讯作者：
P. Cartigny
影响因子：
5.8
作者：
Koppers, Anthony A. P.;Russell, Jamie A.;Hart, Stanley R.
通讯作者：
Hart, Stanley R.
影响因子：
3.5
作者：
J. Moore;B. P. Fabbi
通讯作者：
J. Moore;B. P. Fabbi
氧化萨摩亚熔体的多种硫同位素组成以及硫同位素“地幔阵列”在化学地球动力学中的意义
影响因子：
5.3
作者：
Jabrane Labidi;P. Cartigny;M. Jackson
通讯作者：
M. Jackson