江南造山带存在新元古代(~850 Ma)俯冲作用——来自皖南SSZ型蛇绿岩锆石SHRIMP U-Pb年龄证据

被引:87
作者
丁炳华
史仁灯
支霞臣
郑磊
陈雷
机构
[1] 中国科学技术大学地球与空间科学学院中国科学院壳幔物质和环境重点实验室
关键词
SHRIMPU-Pb年龄; SSZ型蛇绿岩; 新元古代; 江南造山带;
D O I
暂无
中图分类号
P588.125 [];
学科分类号
070901 ;
摘要
皖南伏川蛇绿岩是江南造山带上出露最完整的蛇绿岩,主要由地幔橄榄岩、堆晶岩、枕状熔岩和少量硅质岩组成。地幔橄榄岩主要是方辉橄榄岩,具有U型的稀土元素配分模式,副矿物尖晶石的Cr#较高(54~60),堆晶岩组合为纯橄岩-易剥橄榄岩-辉长岩(DPG型),这些特征指示伏川蛇绿岩形成于俯冲带之上的构造环境,属SSZ型蛇绿岩。堆晶岩异剥橄榄岩的锆石SHRIMP U-Pb年龄为827±9 Ma(n=12,MSWD=1.4),侵入到方辉橄榄岩中的辉长岩岩脉的锆石SHRIMP U-Pb年龄为848±12 Ma(n=7,MSWD=1.9),说明扬子板块和华夏板块至少在848 Ma之前就开始拼合,它们之间的古大洋在新元古代(850 Ma)之前就已经俯冲削减。
引用
收藏
页码:375 / 388
页数:14
相关论文
共 26 条
[11]  
中国大地构造学纲要[M]. 地质出版社 , 万天丰著, 2004
[12]  
蛇绿岩与地球动力学研究[M]. 地质出版社 , 张旗主编, 1996
[13]  
Tethyan vs. Cordilleran ophiolites: a reappraisal of distinctive tectono-magmatic features of supra-subduction complexes in relation to the subduction mode[J] . Luigi Beccaluva,Massimo Coltorti,Giuseppe Giunta,Franca Siena.Tectonophysics . 2004 (1)
[14]  
Subduction initiation: spontaneous and induced[J] . Robert J. Stern.Earth and Planetary Science Letters . 2004 (3)
[15]  
TEMORA 1: a new zircon standard for Phanerozoic U–Pb geochronology[J] . Lance P Black,Sandra L Kamo,Charlotte M Allen,John N Aleinikoff,Donald W Davis,Russell J Korsch,Chris Foudoulis.Chemical Geology . 2003 (1)
[16]  
Petrogenesis and geotectonic setting of ultramafic rocks in the Eastern Alps: constraints from geochemistry[J] . F Melcher,T Meisel,J Puhl,F Koller.LITHOS . 2002 (1)
[17]  
Geochemical and SmNd isotopic study of Neoproterozoic ophiolites from southeastern China: petrogenesis and tectonic implications[J] . Xian-hua Li,Jian-xin Zhao,Malcolm T. McCulloch,Guo-qing Zhou,Feng-ming Xing.Precambrian Research . 1997 (1)
[18]   CHROMIAN SPINEL AS A PETROGENETIC INDICATOR IN ABYSSAL AND ALPINE-TYPE PERIDOTITES AND SPATIALLY ASSOCIATED LAVAS [J].
DICK, HJB ;
BULLEN, T .
CONTRIBUTIONS TO MINERALOGY AND PETROLOGY, 1984, 86 (01) :54-76
[19]  
赣东北晚元古代蛇绿岩套的Sm-Nd同位素年龄及原始构造环境 .2 徐备,乔广生. 南京大学学报 . 1989
[20]  
Marginal Basin Geology .2 Pearce J A,Lippard SJ,Roberts S. Geological Society of London Special Publication . 1984