Discovery of Enclaves from Cenozoic Pulu Volcanic Rocks of West Kunlun Mountains and Their Geological Implications
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摘要: 报道了在西昆仑于田县南普鲁火山岩首次发现的包体的产出特征与矿物组成特征, 提出其包体为岩浆在高位岩浆房中分离结晶作用形成的堆积相, 并估算了其原始岩浆的成分特征, 结果表明: 其原始岩浆和处于同一火山带的康西瓦火山岩相似, 暗示了它们来自于同一源区.但在高位岩浆房中, 随着分离结晶作用的进行, 岩浆的温度和氧逸度逐渐降低.Abstract: In this paper, we report the occurrence and mineral components of the enclaves, firstly discovered in the Cenozoic Pulu volcanic rocks in West Kunlun Mountains, and propose that the enclaves are accumulated by fractional crystallization within high level magma chamber. In addition, we have calculated the compositions of its primary magma. The calculated compositions are similar to those of the Kangxiwa volcanic rocks that belong to a same volcanic belt with the Pulu volcanic region, suggesting that they could have originated from the same source region. However, the temperatures and oxygen fugacity of magmas at high level magma chamber decreased along with fractional crystallization.
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Key words:
- enclave /
- fractional crystallization /
- volcanic rocks /
- West Kunlun Mountains
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表 1 西昆仑普鲁火山岩中的包体矿物电子探针分析结果
Table 1. Microprobe analysis of minerals in enclave from Pulu volcanic rocks in West Kunlun Mountain
表 2 西昆仑普鲁火山岩中的斑晶矿物电子探针分析结果
Table 2. Microprobe analysis of phenocrysts from Pulu volcanic rocks in West Kunlun Mountain
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