TEM and HRTEM study of microstructures in omphacite from UHP eclogites at Shima, Dabie Mountains, China

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	TEM and HRTEM study of microstructures in omphacite from UHP eclogites at Shima, Dabie Mountains, China
	X. L. Wu; Y. J. Han; D. W. Meng; W. R. Yang; D. X. Li
	2000
发表期刊	Acta Geologica Sinica-English Edition
ISSN	1000-9515
卷号	74 期号:2 页码:154-162
摘要	Transmission electron microscope (TEM) and high resolution transmission electron microscope (HRTEM) analyses have been performed on omphacite from ultra-high pressure (UHP) eclogites at the locality of Shima, Dabie Mountains, China. TEM reveals that the microstructures consist dominantly of dislocation substructures, including free dislocations, loops, tiltwalls, dislocation tangles and subboundaries. They were produced by high-temperature ductile deformation, of which the main mechanism was dislocation creep. Antiphase domain (APD) boundaries are common planar defects; an age of 470 +/- 6 Ma for UHP eclogite formation has been obtained from the equiaxial size of APDs in ordered omphacites from Shima, coincident with ages given by single-zircon U-Pb dating (471 +/- 2 Ma). HRTEM reveals C2/c and P2/n space groups in different parts of one single omphacite crystal, and no exsolution is observed in the studied samples, which is attributed to rapid cooling. It is suggested that the UHP eclogites underwent a long period of annealing at high temperatures, followed by relatively rapid cooling. These data provide valuable information for the formation and exhumation mechanism of UHP eclogites in the Dabie high-pressure (HP) and UHP metamorphic belt.
部门归属	china univ geosci, test ctr, wuhan 430074, hubei, peoples r china. china univ geosci, fac earth sci, wuhan 430074, hubei, peoples r china. chinese acad sci, inst met res, atom imaging solids lab, shenyang 110015, liaoning, peoples r china.;wu, xl (reprint author), china univ geosci, test ctr, wuhan 430074, hubei, peoples r china
关键词	Uhp Eclogite Omphacite Tem And hrTem Dabie Mountains High-temperature Deformation Naturally Deformed Omphacites Diopside Single-crystal Dislocation Glide Transformation Consequences Mechanisms Rocks Shan
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WOS记录号	WOS:000088935900008
引用统计	被引频次：6[WOS] [WOS记录] [WOS相关记录]
文献类型	期刊论文
条目标识符	http://ir.imr.ac.cn/handle/321006/37209
专题	中国科学院金属研究所
推荐引用方式 GB/T 7714	X. L. Wu,Y. J. Han,D. W. Meng,et al. TEM and HRTEM study of microstructures in omphacite from UHP eclogites at Shima, Dabie Mountains, China[J]. Acta Geologica Sinica-English Edition,2000,74(2):154-162.
APA	X. L. Wu,Y. J. Han,D. W. Meng,W. R. Yang,&D. X. Li.(2000).TEM and HRTEM study of microstructures in omphacite from UHP eclogites at Shima, Dabie Mountains, China.Acta Geologica Sinica-English Edition,74(2),154-162.
MLA	X. L. Wu,et al."TEM and HRTEM study of microstructures in omphacite from UHP eclogites at Shima, Dabie Mountains, China".Acta Geologica Sinica-English Edition 74.2(2000):154-162.