方辉橄榄岩
- 网络harzburgite
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主要岩石类型是方辉橄榄岩和纯橄榄岩,二辉橄榄岩极少(单斜辉石含量5~7%),具有典型的变质岩结构构造特征,矿物显微塑性变形普遍发育。
Lithologic types of the massifs are mainly harzburgite and dunite , with subordinated lherzolite ( orthopyroxene : 5 ~ 7 % ) . The textures and structures are similar to those of metamorphic rocks , and micro - plastic deformation of minerals is ubiquitous .
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地幔橄榄岩主要是方辉橄榄岩,其主要氧化物成分较为单一,具LREE富集、Eu亏损的U形REE配分模式,亏损强不相容元素;
The mantle peridotite is composed mainly of harzburgite , which shows a narrow range in the major elements , enriched light rare earth elements ( LREE ), U-type REE patterns with negative Eu anomaly , and strongly depleted incompatibility elements .
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海山顶部的岩石是由蛇纹石化超镁铁质方辉橄榄岩组成。
The rocks at the top of the seamount consist of serpentinized ultramafic harzburgite .
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吉林双辽地区古近纪玄武岩中一方辉橄榄岩包体记录了上地幔交代作用的信息。
A harzburgite xenolith sample from Paleogene basalts in Shuangliao area of Jilin Province records the information of upper mantle metasomatism .
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变质方辉橄榄岩的微量元素地球化学及矿物化学特征表明,应为亏损的残余地幔产物。
Trace element geochemistry and mineral chemistry studies on the metamorphosed harzburgite indicate that it is the relict of the depleted mantle .
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这些特征表明该方辉橄榄岩应代表洋壳下伏地幔橄榄岩,从而揭示大陆造山带从早期的大洋俯冲消亡到大陆俯冲碰撞的完整过程。
The presence of the oceanic harzburgite in continental-type UHP belt reveals an integrated process of continental orogenic belt from oceanic lithospheric subduction to subsequent continental subduction and collision .
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上地幔部分熔融作用不仅控制了上地幔岩石类型演化(二辉橄榄岩→方辉橄榄岩→纯橄榄岩),同时它对铬铁矿的预富集起着关键作用。
The partial melting of the upper mantle not only controlled the evolution of mantle rock types ( lherzolite → harzber-gite → dunite ) but also played a critical role for chromite preconcentration .