Rb-Sr and Sm-Nd Isotopic Compositions of the Kangding Complexes and Their Significances

Abstract

Abstract:

Through systematic measurement of Rb-Sr and Sm-Nd isotopic compositions in three sets of hornblende, biotite, plagioclase, K-feldspar separates extracted from tonalite，biotite-hornblende-plagioclase gneiss, and hornblende leptite and their correspond whole rocks in the Kangding-Mianning area, Sichuan Province,together with U-Pb ages of zircons in the rocks, the results indicate that their original crystallization ages of magmas cannot be ascertained by Rb-Sr and Sm-Nd isotopic systematics because of complicated history of formation and metamorphism. Fitted~700 Ma isochrones by Rb-Sr and Sm-Nd isotopic compositions of mineral separates and their whole rocks suggest metamorphism age of amphibolitesupperamphibolite facies. Because of partial resetting of Sm-Nd isotopic system during the processes, Sm-Nd isochrones give rise to older meaningless mixed age usually. The Kangding complexes had not experienced metamorphism of granulitic facies after magma crystallization. The lenticular granulitic bodies may be the relict products of metamorphosed oceanic crustal component after partial melting during subduction of newly formed oceanic crust underneath the Yangtze craton in Neoproterozoic period by the Rodinia super-continent’s break-off. The metamorphosed oceanic crustal rocks, previously underplating mafic rocks, and metamorphosed felsic basement rocks of the Yangtze craton began to partially melt when the subducted oceanic plate was broken off and up-welling of asthenospheric material. TTG(tonalite-trondjemite-granodiorite)association was formed by mixing of dominant(>70%)magma derived from partial melting of metamorphic mafic rocks with that from partial melting of metamorphic felsic basement rocks.

Key words: the Kangding complexes, Rb-Sr isotopes, Sm-Nd isotopes, petrogenesis

CLC Number:

P588.1

CHEN Yue-Long WANG Zhong LUO Zhao-Hua LI Da-Feng DIAO Dun-Xiang. Rb-Sr and Sm-Nd Isotopic Compositions of the Kangding Complexes and Their Significances[J]. Geoscience, 2008, 22(5): 707-714.

References

[1]马玉孝，王大可，纪相田，等.川西攀枝花—西昌地区结晶基底的划分\[J\].地质通报，2003，22(9):688-694.

［2］辜学达，刘啸虎.四川省岩石地层\[M\].武汉：中国地质大学出版社，1979.

［3］Zhou M F, Yan D P, Kennedy A K, et al. SHRIMP UPb zircon geochronological and geochemical evidence for Neoproterozoic arcmagmatism along the western margin of the Yangtze Block, South China\[J\]. Earth Planet Sci Lett, 2002,196:51-67.

［4］李献华，李正祥，周汉文,等.川西南关刀山岩体的SHRIMP锆石UPb年龄、元素和Nd同位素地球化学——岩石成因与构造意义\[J\].中国科学：D辑，2002, 32(增刊)：60-68.

［5］Li Z X, Li X H, Kinny P D, et al. Geochronology of Neoproterozoic synrift magmatism in the Yangtze Craton, South China and correlations with other continents:evidence for a mantle supperplume that broke up Rodinia\[J\]. Precam Res, 2003, 122:85-109.

［6］陈岳龙，罗照华，赵俊香，等.从锆石SHRIMP年龄及岩石地球化学特征论四川冕宁康定杂岩的成因\[J\].中国科学：D辑，2004, 34(8)：687-697.

［7］陈岳龙，罗照华，刘翠.对扬子克拉通西缘康定—冕宁变质基底的新认识——来自Nd同位素的证据\[J\].地球科学，2001, 26(3)：279-285.

［8］赵俊香，陈岳龙，李志红.康定杂岩锆石SHRIMP UPb定年及其地质意义\[J\].现代地质，2006, 20(3)：378-385.

［9］杜利林，耿元生，杨崇辉，等.扬子地台西缘新元古代TTG的厘定及其意义［J］.岩石矿物学杂志，2006, 25(4):273-281.

［10］Li Z X, Li X H, Kinny P D, et al. The breakup of Rodinia: did it start with a mantle plume beneath South China?\[J\] Earth Planet Sci Lett, 1999, 173:171-181.

［11］林广春，李献华，李武显.川西新元古代基性岩墙群的SHRIMP锆石UPb年龄、元素和NdHf同位素地球化学：岩石成因与构造意义\[J\].中国科学：D辑, 2006, 36(7)：630－645.

［12］李献华，李正祥，周汉文，等.川西新元古代玄武质岩浆岩的锆石UPb年代学、元素和Nd同位素研究：岩石成因与地球动力学意义\[J\].地学前缘，2002, 9(4)：329－338.

［13］李献华，周汉文，李正祥，等.川西新元古代双峰式火山岩成因的微量元素和SmNd同位素制约及其大地构造意义\[J\].地质科学，2002, 37(3)：264-276.

［14］韩吟文，马振东，张宏飞，等.地球化学\[M\].北京：地质出版社，2003.

［15］李大鹏，陈岳龙，罗照华.康定杂岩黑云母、角闪石39Ar－40Ar年龄及其意义\[J\].岩石学报，2006, 22(11):2753-2761.

［16］贺节明.康滇灰色片麻岩\[M\].重庆：重庆出版社，1988.

［17］张宗清，叶笑江.稀土元素的质谱稀释分析和143Nd／144Nd比值的精确测定方法\[J\].中国地质科学院地质研究所所刊，1987,17：108-128.

［18］叶笑江，张宗清. Nd比值测定中的Sm、Nd分离：HDEHP分离法\[J\].分析测试通报，1990(3)：6－9.

［19］陈岳龙，杨忠芳，赵志丹.同位素地质年代学与地球化学\[M\].北京：地质出版社，2005.

［20］Ludwig K R. User’s Manual for Isoplot 300, A Geochronological Toolkit for Microsoft Excel\[M\]. Berkeley：Geochronology Center Special Publication, 2003：25-39.

［21］杜利林，耿元生，杨崇辉，等.扬子地台西缘康定群的再认识：来自地球化学和年代学证据\[J\].地质学报，2007, 81(11):1562-1577.

［22］牛宝贵，和政军，任纪舜，等.秦岭地区陡岭—小茅岭隆起带西段几个岩体的SHRIMP锆石UPb测年及其地质意义\[J\]. 地质论评，2006, 52(6):826-835.

［23］许志琴，刘福来，戚学祥，等.南苏鲁超高压变质地体中罗迪尼亚超大陆裂解事件的记录\[J\].岩石学报，2006,22(7)：1745－1760.

［24］叶建国，刘福来.中国大陆科学钻探工程主孔斜长角闪岩中锆石的SHRIMP UPb定年及其地质意义\[J\].地质通报，2008, 27(5):589-598.

［25］徐士进，于航波，王汝成，等.川西沙坝麻粒岩的SmNd和RbSr同位素年龄及其地质意义\[J\].高校地质学报，2002, 8(4):399-406.

［26］徐士进，刘文中，王汝成，等.攀西微古陆块的变质演化与地壳抬升史——中基性麻粒岩的SmNd,40Ar/39Ar和FT年龄证据\[J\].中国科学：D辑, 2003, 33(11):1037-1049.

［27］刘文中.扬子陆块西缘康定杂岩的形成时代和构造环境\[J\].安徽理工大学学报：自然科学版，2006, 26(4)：1-5.

［28］Rudnick R L, Gao S. Composition of the Continental Crust［M］// Holland H D,Turekian K K. Treatise on Geochemistry,Volume 3-The Crust. Oxford:ElsevierPergamon, 2003：1-64.

［29］Watson E B, Harrison T M. Zircon saturation revised:temperature and composition effects in a variety of crustal magma types\[J\]. Earth Planet Sci Lett, 1983, 64:295-304.

［30］曾宪教，徐先哲，袁蔺平. 四川冕宁沙坝地区康定杂岩中的麻粒岩岩石学和地球化学特征\[M\]//张云湘.中国攀西裂谷文集(1).北京：地质出版社，1985.

［31］Ghiorso M S , Sack R O. Chemical masstransfer in magmatic process IV. A revised and internally consistent thermodynamic model for interpolation and extrapolation of liquidsolid equilibria in magmatic systems at elevatedtemperature and pressure\[J\]. Contributions to Mineralogy and Petrology,1995, 119(2-3): 197-212.

［32］Asimow P D, Ghiorso M S. Algorithmic modifications extending MELTs to calculate ubsolidus phase relations\[J\]. American Mineralogist, 1998, 83(9-10): 1127-1132.

［33］Smith P M, Asimow P D. Adiabat_1ph: A new public frontend to the MELTs, pMELTs, and pHMELTs models\[J\].Geochem,Geophys,Geosyst, 2005,6,art.No.Q02004,doi:101029/2004GC000816.

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