Geochemistry of volcanic glasses from the Louisville Seamount Trail (IODP Expedition 330): Implications for eruption environments and mantle melting
Geochemistry of volcanic glasses from the Louisville Seamount Trail (IODP Expedition 330): Implications for eruption environments and mantle melting
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路易斯维尔海山小道（IODP Expedition 330）火山玻璃的地球化学：对喷发环境和地幔融化的影响
DOI：
10.1002/2013gc005086
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发表时间：
2014
期刊：
影响因子：
3.7
通讯作者：
Brandl
中科院分区：
文献类型：
--
作者：
Nichols;Brandl
对在西南太平洋路易斯维尔海山小道钻探过程中发现的四个火山玻璃进行了常量、痕量和挥发性元素(H2O、CO2、S和氯)和氧同位素的分析。与其他大洋岛屿环境相比，它们在地球化学上是均一的，没有提供夏威夷所特有的拉斑玄武岩阶段的证据。部分熔融的程度和深度在1-3 Ma期间保持不变，以钻孔为代表，并沿链状分布，超过数百万年。唯一的例外是Hadar Guyot，其成分表明富集源的小度优先熔融，可能是因为它在最古老和最厚的岩石圈喷发。来自晚期火山碎屑岩的不相容元素富玻璃意味着随着火山离开熔融异常，熔融程度较低。来自整个火成岩基底的火山碎屑玻璃被脱气，这表明它是在浅海底喷发(<；20 Mbsl)或水下水流进入海洋时产生的。由于淬火后的下坡运动，钻探深度可能不再反映相对年龄。晚期火山碎屑中较高的挥发分含量表明海底喷发在118-258 Mbsl，喷发时建筑物下沉到海平面以下，或在侧翼喷发中生成。来自侵入体边缘的玻璃表明，∼位于地表以下100m处。达到这些古淬灭深度所需的抬升和随后达到其当前深度的下沉超过了正常大洋岩石圈的预期，这与Guyot喷发时路易斯维尔熔融异常比正常软流层高<；100℃是一致的。
Volcanic glasses recovered from four guyots during drilling along the Louisville Seamount Trail, southwest Pacific, have been analyzed for major, trace, and volatile elements (H2O, CO2, S, and Cl), and oxygen isotopes. Compared to other oceanic island settings, they are geochemically homogeneous, providing no evidence of the tholeiitic stage that characterizes Hawai'i. The degrees and depth of partial melting remained constant over 1–3 Ma represented by the drill holes, and along‐chain over several million years. The only exception is Hadar Guyot with compositions that suggest small degree preferential melting of an enriched source, possibly because it erupted on the oldest and thickest lithosphere. Incompatible element enriched glass from late‐stage volcaniclastics implies lower degrees of melting as the volcanoes moved off the melting anomaly. Volcaniclastic glasses from throughout the igneous basement are degassed suggesting generation during shallow submarine eruptions (<20 mbsl) or as subaerial flows entered the sea. Drill depths may no longer reflect relative age due to postquench downslope movement. Higher volatile contents in late‐stage volcaniclastics indicate submarine eruptions at 118–258 mbsl and subsidence of the edifices below sea level by the time they erupted, or generation in flank eruptions. Glass from intrusion margins suggests emplacement ∼100 m below the surface. The required uplift to achieve these paleo‐quench depths and the subsequent subsidence to reach their current depths exceeds that expected for normal oceanic lithosphere, consistent with the Louisville melting anomaly being <100°C hotter than normal asthenosphere at 50–70 Ma when the guyots were erupted.
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西南太平洋路易斯维尔热点链的地理和历史
DOI：
--
发表时间：
1988
期刊：
影响因子：
--
作者：
P. Lonsdale
通讯作者：
P. Lonsdale
影响因子：
56.9
作者：
J. Tarduno;R. Duncan;D. Scholl;R. Cottrell;B. Steinberger;T. Thordarson;B. Kerr;C. Neal;F. Frey-F.
通讯作者：
J. Tarduno;R. Duncan;D. Scholl;R. Cottrell;B. Steinberger;T. Thordarson;B. Kerr;C. Neal;F. Frey-F.
影响因子：
5.3
作者：
G. Ito;P. Clift
通讯作者：
G. Ito;P. Clift
影响因子：
3.7
作者：
K. Simons;J. Dixon;J. Schilling;R. Kingsley;R. Poreda
通讯作者：
K. Simons;J. Dixon;J. Schilling;R. Kingsley;R. Poreda
翁通爪哇高原海底玄武岩玻璃中的挥发物（ODP Leg 192）：对岩浆过程和源区成分的影响
DOI：
--
发表时间：
2002
期刊：
Geological Society Special Publication
影响因子：
--
作者：
J. Roberge;R. White;P. Wallace
通讯作者：
P. Wallace