滇西南那邦变质基性岩地球化学与俯冲板片裂离

doi:10.3321/j.issn:1000-0569.2000.03.017

CORC > 北京大学 > 地球与空间科学学院

	滇西南那邦变质基性岩地球化学与俯冲板片裂离; Geochemistry and genesis of Nabang metamorphic basalt, southwest Yunnan, China: implications for the subducted slab break-off.
	季建清 ; 钟大赉 ; 陈昌勇
刊名	岩石学报
	2000
关键词	变质基性岩洋壳残片密支那缝合带板片裂离那邦滇西 metamorphic basalt oceanic relict Myitkyina suture slab break-off Nabang west Yunnan
DOI	10.3321/j.issn:1000-0569.2000.03.017
英文摘要	中缅边界那邦麻粒岩相变质基性岩地球化学特征研究表明其原岩是岩浆岩 ,并具有 MORB的特性 ,其岩石化学具有以下特征 :岩石的 TFe O/ Mg O值低 (1.10～ 2 .17) ,AFM图解上显示拉斑玄武岩演化趋势 ;Ti O2 含量 (1.14%～ 1.81% )高于岛弧拉斑玄武岩。多数微量元素与大洋中脊拉斑玄武岩含量相当 ,Nd、Ta值高于岛弧拉斑玄武岩。稀土元素配分图显示轻稀土亏损、重稀土较有富集的配分型式 ,稀土元素和总量 (ΣREE)值十倍于球粒陨石 (2 4～ 5 0μg/ g) ,(L a/ Sm ) N=0 .43～ 0 .75 ,(L a/ Yb) N=0 .45～ 0...; The Nabang metamorphic basalt is discovered recently on the border of China and Burma. The majoy, trace and rare earth element characteristics of Nabang metamorphic basalt have been investigated. All studied socks are depleted in light rare earth elements (LREE) with Sigma REE= 24 similar to 50 mu g/g, (La/Sm)(N) = 0.43 similar to 0.75 the same and (La/Yb)(N) = 0.45 similar to 0.74. Ti2O, Nb and Ta show that the Nabang metamorphic rocks are different from island-are basalt as shown by the geochemical diagrams. The Nd-Sr isotope data show a clear signature of a depleted mantle source similar to N-MORB with Sr-87/Sr-86 = 0.704 similar to 0.705, Nd-143/Nd-144 = 0.5129 similar to 0.5132. epsilon(Nd) = +4.85 similar to +9.67. Combining with its geochronological results and geological background, it can be concluded that the Nabang metamorphic basalt is related to Myitkyina suture, east Burma. The Nabang metamorphic basalt may be an evidence of slab-breakoff of Neo-Tethys subducted upper oceanic crust.; http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000089084300017&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701 ; SCI(E); 中文核心期刊要目总览(PKU); 中国科学引文数据库(CSCD); 9; 03; 433-442; 16
语种	中文
内容类型	期刊论文
源URL	[http://ir.pku.edu.cn/handle/20.500.11897/48839]
专题	地球与空间科学学院
推荐引用方式 GB/T 7714	季建清,钟大赉,陈昌勇. 滇西南那邦变质基性岩地球化学与俯冲板片裂离, Geochemistry and genesis of Nabang metamorphic basalt, southwest Yunnan, China: implications for the subducted slab break-off.[J]. 岩石学报,2000.
APA	季建清,钟大赉,&陈昌勇.(2000).滇西南那邦变质基性岩地球化学与俯冲板片裂离.岩石学报.
MLA	季建清,et al."滇西南那邦变质基性岩地球化学与俯冲板片裂离".岩石学报 (2000).