新元古代Rodinia超大陆裂解事件在扬子北东缘的最初响应:东海片麻状碱性花岗岩的锆石U-Pb年代学及Nd同位素制约

被引:23
作者
胡建
邱检生
王汝成
蒋少涌
于津海
倪培
机构
[1] 南京大学成矿作用国家重点实验室
基金
国家创新研究群体科学基金;
关键词
片麻状碱性花岗岩; LA-ICP-MS 锆石 U-Pb 定年; Nd 同位素示踪; Rodinia 超大陆裂解; 江苏东海;
D O I
暂无
中图分类号
P588.121 []; P597.3 [];
学科分类号
摘要
东海片麻状碱性花岗岩是扬子克拉通北东缘最具代表性的含碱性铁镁矿物的过碱性 A 型花岗岩。高精度的LA-ICP-MS 锆石 U-Pb 定年结果表明,这些岩石形成于新元古代中期770Ma 左右,并在约250Ma 时经历超高压变质作用,之后又于210Ma 左右遭受了大规模的角闪岩相退变质作用的改造。Nd 同位素示踪表明东海片麻状碱性花岗岩具有相对偏高的εNd(t)值(+1.4~-5.91),指示其应是成熟度较低的下地壳部分熔融的产物,但不排除部分岩体在成岩过程中可能有少量幔源物质卷入。综合 Rodinia 超大陆古地理复原资料,推测扬子板块北东缘自新元古早期以来一直为接受大洋板块俯冲的活动大陆边缘。形成于新元古代中期的东海片麻状碱性花岗岩属 A2型花岗岩,为弧后拉张背景下岩浆活动的产物,该类岩石的产出代表了 Rodinia 超大陆裂解事件在该地区的最初响应。
引用
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页码:1321 / 1333
页数:13
相关论文
共 59 条
[51]  
Ages of ultrahigh pressure metamorphism and protolith orthogneisses from the eastern Dabie Shan: U/Pb zircon geochronology[J] . D.B. Rowley,F. Xue,R.D. Tucker,Z.X. Peng,J. Baker,A. Davis.Earth and Planetary Science Letters . 1997 (3)
[52]  
Palaeomagnetic study of Neoproterozoic glacial rocks of the Yangzi Block: palaeolatitude and configuration of South China in the late Proterozoic Supercontinent[J] . Qi Rui Zhang,J.D.A. Piper.Precambrian Research . 1997 (3)
[53]  
The Grenville Orogenic Cycle (ca. 1350-1000 Ma): an Adirondack perspective[J] . James McLelland,J.Stephen Daly,Jonathan M. McLelland.Tectonophysics . 1996 (1)
[54]  
Dehydration-melting of amphibolite at 10 kbar: the effects of temperature and time[J] . Michael B. Wolf,Peter J. Wyllie.Contributions to Mineralogy and Petrology . 1994 (4)
[55]  
Magma sources for Mesozoic anorogenic granites of the White Mountain magma series, New England, USA[J] . K. A. Foland,J. C. Allen.Contributions to Mineralogy and Petrology . 1991 (2)
[56]   POST-COLLISIONAL ALKALINE GRANITES [J].
SYLVESTER, PJ .
JOURNAL OF GEOLOGY, 1989, 97 (03) :261-280
[57]  
Origin of infracrustal (I-type) granite magmas[J] . B. W. Chappell,W. E. Stephens.Transactions of the Royal Society of Edinburgh: E . 1988 (2-3)
[58]  
A-type granites: geochemical characteristics, discrimination and petrogenesis[J] . Joseph B. Whalen,Kenneth L. Currie,Bruce W. Chappell.Contributions to Mineralogy and Petrology . 1987 (4)
[59]   NATURE AND ORIGIN OF A-TYPE GRANITES WITH PARTICULAR REFERENCE TO SOUTHEASTERN AUSTRALIA [J].
COLLINS, WJ ;
BEAMS, SD ;
WHITE, AJR ;
CHAPPELL, BW .
CONTRIBUTIONS TO MINERALOGY AND PETROLOGY, 1982, 80 (02) :189-200