Geochemistry and age of seamounts in the West Pacific: mantle processes and petrogenetic implications
Geochemistry and age of seamounts in the West Pacific: mantle processes and petrogenetic implications
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西太平洋海山的地球化学和年龄：地幔过程和岩石成因意义
DOI：
10.1007/s13131-019-1371-0
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发表时间：
2019-01
影响因子：
1.4
通讯作者：
Limei Tang
中科院分区：
文献类型：
--
作者：
Limei Tang
对海山的研究为了解板内火山活动提供了一些最好的限制，海山的样本揭示了海洋地幔地球化学构成的关键证据。西太平洋海山区仍有许多海山尚未得到研究，这意味着它们的年龄和地球化学仍然未知。通过年龄和地球化学数据调查，更好地了解这些海山痕迹及其演变历史，将有助于更好地了解太平洋板块下的地质过程。本文提供了西太平洋海底保护区四座海山七块玄武岩的新40 Ar/39 Ar年龄、微量元素和Sr-Nd-Pb同位素数据。岩石化学成分均为大洋岛碱性玄武岩（OIA型），橄榄石斑晶分析表明，岩浆演化过程中经历了强烈的橄榄石分馏作用，由橄榄石+斜长石向橄榄石+斜长石+单斜辉石过渡。稀土元素（REE）模式和蜘蛛图在本研究中的样品显示OIB（洋岛玄武岩）的行为。87 Sr/86 Sr比值范围为0.70460 ~ 0.70624，206 Pb/204 Pb比值范围为18.241 ~ 18.599，143 Nd/144 Nd比值范围为0.512646 ~ 0.512826，表明岩浆源区为EMI ~ EMII。最后，新的40 Ar/39 Ar年龄数据显示，这些海山形成于~97和~106 Ma，表明有些海山可能经历了与麦哲伦海山遗迹东部海山相同的形成过程，但其他海山可能有不同的起源。
Research on seamounts provides some of the best constraints for understanding intraplate volcanism, and samples from seamounts reveal crucial evidence about the geochemical makeup of the oceanic mantle. There are still many seamounts in the West Pacific Seamount Province (WPSP) that have not been studied, meaning their ages and geochemistry remain unknown. A better understanding of these seamount trails and their evolutionary history, investigated with age and geochemistry data, will enable better understanding of the geological processes operating underneath the Pacific Ocean Plate. Here, new40Ar/39Ar ages and trace element and Sr-Nd-Pb isotopic data for seven basalt rocks from four seamounts in the WPSP are provided. Chemically, these rocks are all Oceanic Island Alkali basalt (OIA type); analysis of olivine phenocrysts shows that the magmas experienced strong olivine fractionation and changed from olivine + plagioclase to olivine + plagioclase + clinopyroxene cotectic during their evolution. Rare earth element (REE) patterns and a spider diagram of the samples in this study show OIB (Ocean Island Basalt) like behavior. The range of87Sr/86Sr values is from 0.704 60 to 0.706 24, the range of206Pb/204Pb values is from 18.241 to 18.599, and the range of143Nd/144Nd values is from 0.512 646 to 0.512 826; together, these values indicate magma sources ranging from EMI to EMII. Finally, new40Ar/39Ar age data show that these seamounts formed at ~97 and ~106 Ma, indicating that some may have undergone the same formation processes as seamounts in the eastern part of the Magellan Seamount Trail, but other seamounts likely have different origins.
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DOI：
10.1002/9781444324860.ch1
发表时间：
2010-08
期刊：
--
影响因子：
--
作者：
G. Foulger
通讯作者：
G. Foulger
DOI：
10.2973/odp.proc.sr.144.031.1995
发表时间：
1995
期刊：
--
影响因子：
--
作者：
A. Koppers;H. Staudigel;D. Christie;J. Dieu;M. Pringle
通讯作者：
A. Koppers;H. Staudigel;D. Christie;J. Dieu;M. Pringle
影响因子：
3.5
作者：
S. Révillon;N. Arndt;E. Hallot;A. Kerr;J. Tarney
通讯作者：
S. Révillon;N. Arndt;E. Hallot;A. Kerr;J. Tarney
影响因子：
1.4
作者：
Jun Zhao;Haisheng Zhang;Guanghai Wu;Bing Lu;I. Pulyaeva;Haifeng Zhang;Xuehui Pang
通讯作者：
Jun Zhao;Haisheng Zhang;Guanghai Wu;Bing Lu;I. Pulyaeva;Haifeng Zhang;Xuehui Pang
影响因子：
56.9
作者：
A. Koppers;H. Staudigel
通讯作者：
A. Koppers;H. Staudigel