气候变化领域集成服务门户(CCPortal): Discovery of Cenozoic magnetite volcanic rock in High Himalaya and its tectonic significance

CCPortal

	Discovery of Cenozoic magnetite volcanic rock in High Himalaya and its tectonic significance
	Liu XiaoHan; Tong LaiXi; Shi RenDeng; Li GuangWei; Chen ShengSheng; Zhou XueJun; Liu Zhao
通讯作者	Liu, XH (通讯作者)
发表日期	2018
ISSN	1000-0569
EISSN	2095-8927
起始页码	1876
结束页码	1884
卷号	34 期号:7
英文摘要	Late Cenozoic ultra-mafic magnetite-rich volcanic rocks in the High Himalaya metamorphic belt, southern Tibet, are firstly reported in this study. The rocks are mainly composed of Fe-olivine, Fe oxides, Fe-garnet and potassic-rich glasses. A few euhedral Fe-spinel inclusions are discovered in the Fe-olivine grains. Vesicular structure, vitro basic porphyritic texture and typical spinifex texture are normally observed in the rocks. The bulk rock composition of the rock has a feature of strong Si-unsaturation (18. 8% similar to 29. 7% SiO2) and extreme Fe-richness (56. 2% 74. 2% Fe2O3T). Geochemical analyses show that it is strong rich in LILE of Th and U, relative depletion in high field strong elements such as Nb, Ta and Ti, and obvious negative anomalies for Sr element, indicating a geochemical process related to subduction. The volcanic lava cuts across the regional gneissic foliation, implying that it was probably formed in a post-collisional intracontinental extensional environment. Further, the Fe-rich and Si-unsaturated feature also indicates that it might be formed as a result of eruption along extentional fault and melting of Fe-rich protolith from a deep source. The volcano probably erupted during Pliocene-Pleistocene (2 similar to 4Ma) , based on its K/Ar ages between 4. 76 similar to 7. 25Ma, and surrounding rocks wrapped by lava with an apatite fission track ( AFT) age of 2. 04 +/- 0. 21Ma. Generally, the volcanic rock provides first volcanic evidence for post-collisional extension in the High Himalaya tectonic belt during Late Cenozoic, which is critical to further understand the tectonic framework of the southern Tibet Plateau and its evolutionary processes.
关键词	KIRUNA-TYPE DEPOSIT ORIGIN ORE
英文关键词	High Himalaya; Late Cenozoic; Fe-rich volcanic rocks; Tectonic significance
语种	英语
WOS研究方向	Geology
WOS类目	Geology
WOS记录号	WOS:000451724300003
来源期刊	ACTA PETROLOGICA SINICA
来源机构	中国科学院青藏高原研究所
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/259206
推荐引用方式 GB/T 7714	Liu XiaoHan,Tong LaiXi,Shi RenDeng,et al. Discovery of Cenozoic magnetite volcanic rock in High Himalaya and its tectonic significance[J]. 中国科学院青藏高原研究所,2018,34(7).
APA	Liu XiaoHan.,Tong LaiXi.,Shi RenDeng.,Li GuangWei.,Chen ShengSheng.,...&Liu Zhao.(2018).Discovery of Cenozoic magnetite volcanic rock in High Himalaya and its tectonic significance.ACTA PETROLOGICA SINICA,34(7).
MLA	Liu XiaoHan,et al."Discovery of Cenozoic magnetite volcanic rock in High Himalaya and its tectonic significance".ACTA PETROLOGICA SINICA 34.7(2018).