Structural changes in silicate melt: A record from high-field strength elements in the Himalayan Cenozoic leucogranites
Structural changes in silicate melt: A record from high-field strength elements in the Himalayan Cenozoic leucogranites
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硅酸盐熔体的结构变化：喜马拉雅新生代淡色花岗岩中高场强元素的记录
DOI：
10.3389/feart.2022.1097537
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发表时间：
2023-01
影响因子：
2.9
通讯作者：
Yaying Wang
中科院分区：
文献类型：
--
作者：
Li-E Gao;Lingsen Zeng;Lilong Yan;Linghao Zhao;Yaying Wang
大多数喜马拉雅新生代浅色花岗岩是经历过不同程度分离结晶的过铝质岩浆。这些浅色花岗岩的特点是其元素组成的不均匀性相对较高。当熔体的Zr/Hf比超过1.20时，Zr（或Hf）与Zr/Hf比的相关性由正向负转变。当Nb/Ta比超过10.5时，Nb先降低后升高，而Ta先缓慢升高后急剧升高。这种系统的地球化学变化与关键副相溶解行为的变化有关，这是硅酸盐熔体结构变化的结果，与分离结晶和。随着花岗质岩浆的演化，熔体结构的变化，如成分参数的变化所示（例如，NBO/T、A/CNK和M/F）以及Zr/Hf和Nb/Ta比率。当Zr/Hf和Nb/Ta分别大于20和5时，NBO/T、M/F和A/CNK先减小后增大，A/NK和C/NK先减小后趋于恒定，Na/K先趋于恒定后增大。此外，熔体结构的实质性变化导致花岗岩粘度的降低，这反过来又导致花岗岩熔体的分离结晶。最后，这种变化导致了喜马拉雅新生代浅色花岗岩中与经济有关的稀有元素的成矿作用。
Most Himalayan Cenozoic leucogranites are peraluminous magmas that have experienced various degrees of fractional crystallization. These leucogranites are characterized by relatively high degrees of heterogeneity in their elemental compositions. As the melt’s Zr/Hf ratio passes ∼20, there is an apparent change from positive to negative in the correlation between Zr (or Hf) and Zr/Hf ratio. As Nb/Ta ratio passes ∼5, Nb first decreases and then increases, but Ta first slowly increases and then drastically increases. Such systematic geochemical variations are related to changes in the dissolution behavior of key accessory phases, which are the consequence of silicate melt structural changes associated with fractional crystallization and. As a granitic magma evolves, changes in the melt structure as shown by changes in the compositional parameters (e.g., NBO/T, A/CNK, and M/F) as well as in Zr/Hf and Nb/Ta ratios. When the melt’s Zr/Hf and Nb/Ta ratio passes 20 and 5, respectively, NBO/T, M/F, and A/CNK first decrease and then increase; A/NK and C/NK first decrease and then become nearly constant; Na/K first becomes nearly constant and then increases. Moreover, a substantial change in the melt structure leads to a decrease in granitic viscosity, which in turn fractional crystallization of the granitic melts. Finally, such changes result in the mineralization of economically relevant rare elements in the Himalayan Cenozoic leucogranites.
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特提斯喜马拉雅地区兰巴淡色花岗岩的岩石成因及河道水流模型的约束
影响因子：
3.5
作者：
Fu-Yuan Wu;Wei-Qiang Ji;Jian-Gang Wang;Chuan-Zhou Liu
通讯作者：
Chuan-Zhou Liu
影响因子：
5.3
作者：
WATSON, EB;HARRISON, TM
通讯作者：
HARRISON, TM
影响因子：
3.9
作者：
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通讯作者：
Y. Bottinga;P. Richet
DOI：
10.18654/1000-0569/2021.10.01
发表时间：
2021
期刊：
岩石学报
影响因子：
--
作者：
高利娥;曾令森;严立龙;高家昊;赵令浩
通讯作者：
赵令浩
影响因子：
3.9
作者：
J. Montel
通讯作者：
J. Montel