柴北缘绿梁山早古生代花岗岩浆作用与高温变质作用的同时性
Contemporaneous of Eady Palaeozoic granite and high temperature metamorphism,Nonh Qaidam Mountains,western China
-
摘要: 采用SHRIMP方法获得绿梁山花岗岩的锆石U-Pb年龄为430±8Ma(12个测点平均),所有测点的Th/U比值均大于0.1,该年龄代表花岗岩的形成年龄.同时获得部分具有核-幔结构的继承锆石,其核部年龄为475～460Ma,Th/U比值为0.01～0.02,为典型的变质锆石,与围岩片麻岩中的锆石类似,反映了花岗岩与片麻岩之间的成因联系.绿梁山花岗岩属于钙碱性系列,SiO2含量为65.63%～74.78%,变化较大,属于过铝质岩石,推测其源岩以沉积岩为主.围岩片麻岩以变质沉积岩为主,可能为花岗岩的主要源岩.花岗岩的(87Sr/86Sr)t为0.71075(t=430Ma),εNd(430Ma)为-5.5～4.6,与围岩片麻岩的Sr-Nd同位素组成存在较大差别,可能反映了花岗岩形成于高温缺水的环境或者成岩时有地幔物质/年轻地壳物质的加入.花岗岩形成时代与片麻岩变质时代的一致性(430Ma),反映了它们为同一区域构造热事件的产物,是俯冲陆壳发生热松弛的记录.
-
-
[1] Black LP, Kamo SL, Aleinikoff J, et al. 2003. TEMORA 1 : A new zircon standard for Phanerozoic U-Pb geochronology. Chemical Geology, 200:155 - 170
[2] Brown M. 2001. Crustal melting and granite magmatism: Key Issues. Phys. Chem. Earth (A), 26(4-5) :201 -212
[3] Chen Y, Ye K, Liu JB and Sun M. 2006. Multistage metamorphism of the Huangtuling granulite, Northern Dabie Orogen, eastern China: Implications for the tectonometamorphic evolution of subducted lower continental crust. J. Metamorphic. Geol. , 24:633 -654
[4] Chen TY, Niu BG, Liu ZG, Fu YL and Ren JS. 1991. Geochronology of Yanshanian magmatism and metamorphism in the Hinterland of the Dabie Mountains and their geologic significance. Acta Geologica Sinica, (4) : 329 -335 (in Chinese with English abstract)
[5] Harris N and Massey J. 1994. Decompression and anatexis of Himalayan metapelites. Tectonics,13 (6) : 1537 - 1546
[6] Hou ZH, Li SG, Chen NS, Li QL and Liu XM. 2005. Sm-Nd and zircon SHRIMP U-Pb dating of Huilanshan mafic granulite in the Dabie Mountains and its zircon trace element geochemistry. Sci. China (Series D), 48:2081 -2091
[7] Jahn BM, Wu FY, Lo CH and Tsai CH. 1999. Crust mantle interaction induced by deep subduction of the continental crust: Geochemical and Sr Nd isotopic evidence from post-collisional mafic uhramafic intrusions of the northern Dabie complex, central China. Chem. Geol., 157:119 - 146
[8] Kalsbeek F, Jepsen H and Nutman AP. 2001. From source migmatites to plutons: Tracking the origin of ca. 435Ma S-type granite in the East Greenland Caledoning orogen. Lithos, 57:1 -21
[9] Leech ML, Singh S, Jain AK, et al. 2005. The onset of India-Asia continental collision: Early, steep subduction required by the timing of UHP metamorphism in the western Himalaya. Earth and Planetary Science Letters, 234:83 -97
[10] Li CN. 1992. Petrology of Trace Element of Igneous. Wuhan: Publishing House of China University of Geosciences, 1 -195 (in Chinese)
[11] Li DW, Liao QA, Yuan YM, et al. 2003. U-Pb dating of zircon from granulites in the central Greater Himalayas. Chinese Science Bulletin, 48(20) : 2176 -2179 (in Chinese)
[12] Liou JG, Tsujimori T, Zhang RY, etal. 2004. Global UHP metamorphism and continental subduction/collision: The Himalaya Model. International Geology Review, 46:1 -27
[13] Ma XD and Chen DL, 2006. LA-ICP-MS zircon U-Pb dating of quatzo- feldspathic gneisses-the country rocks of ultrahigh-pressure metamorphic rocks on the northern margin of the Qaidam basin, Northwest China. Geological Bulletin of China, 25 ( 1 - 2) : 99 - 105 (in Chinese with English abstract)
[14] Ma CQ, Li Z, Ehlers C, Yang KG and Wang R. 1998. A post-collisional magmatic plumbing system: Mesozoic granitoid plutons from the Dabieshan high-pressure and ultrahigh-pressure metamorphic zone, east-central China. Lithos, 45:431 -456
[15] Meng FC, Zhang JX and Yang JS. 2005a. Tectono thermal event of Post- HP/UHP metamorphism in the Xitieshan area of the North Qaidam Mountains, western China: Isotopic and geochemical evidence of granite and gneiss. Acta Petrologica Sinica, 21 ( 1 ) : 45 - 56 ( in Chinese with English abstract)
[16] Meng FC, Zhang JX and Yang JS. 2005b. Subducted continental arc: Geochemical and isotopic evidence of gneisses in the North Qaidam. Acta Geologica Sinica, 79 ( 1 ) :46 - 55 ( in Chinese with English abstract )
[17] Peccerillo A and Taylor SR. 1976. Geochemistry of Eocene calc-alkaline volcanic rocks from the Kastamonu area, Northern Turkey. Contribution to Mineralogy and Petrology, (1) : 64 -81
[18] Searle MP, Parrish RR, Hodges KV, Hurford A, Ayres MW and Whitehouse MJ. 1997. Shisha Pangma leucogranite, South Tibetan Himalaya: Field relations, geochemistry, age, origin, and emplacement. Journal of Geology, 105 : 295 - 317
[19] Song SG, Zhang LF, Niu Y. 2004. Ultra-deep origin of garnet peridotite from the North Qaidam ultrahigh-pressure belt, Northern Tibetan Plateau, NW China. American Mineralogist, 89 : 1330 - 1336
[20] Song SG, Zhang LF, Niu YL. Su L, Jian P and Liu DY. 2005. Geochronology of diamond-bearing zircons from garnet peridotite in the North Qaidam UHPM belt, Northern Tibetan Plateau: A record of complex histories from oceanic lithosphere subduction to continental collision. EPSL, 234 : 99 - 118
[21] Xie Z, Zheng YF, Zhao ZF, Wu YB, Wang ZR, Chen JF, Liu XM and Wu FY. 2006. Mineral isotope evidence for the contemporaneous process of Mesozoic granite emplacement and gneiss metamorphism in the Dabie orogen. Chemical Geology, 231:214 - 235
[22] Yang JS,Xu ZQ, Li HB, Wu CL, Cui JW, Zhang JX and Chen W. 1998. The discovery of eclogite in the northern margin of Qaidam basin, China. Chin. Sci. Bull. , 43 (14) : 1544 - 1549 ( in Chinese )
[23] Yang JJ, Zhu H, Deng JF, Zhou TZ and Lai SC. 1994. The discovery of garnet peridotite in Northern Chaidam Mountains and its significance. Acta Petrologica et Mineralogica, 13 (2) : 97 - 104 (in Chinese with English abstract)
[24] Zeng LS,Saleeby JB and Asimow PD. 2005a. Nd isotope disequilibrium during crustal anatexis: A record from the Goat Ranch migmatite complex, southern Sierra Nevada batholith, California. Geology, 33 (1): 53 -56
[25] Zeng LS, Asimow PD and Saleeby JB. 2005b. Coupling of anatectic reactions and dissolution of accessory and the Sr and Nd isotope systematics of anatectic melts from a metasedimentary source. Geochimica et Cosmochimica Acta, 69 (14) : 3671 - 3682
[26] Zeng LS, Liu J, Gao LE, Xie KJ and Wen L. 2008. Early Oligocene anatexis in the Yardoi gneiss dome, Southern Tibet and geological implication. Chinese Science Bulletin ( in press)
[27] Zhang HF, Harris N, Parrish R, Zhang L and Zhao ZD. 2004. U-Pb ages of Kude and Sajia leucogranites in Sajia dome from North Himalaya and their geological implications. Chinese Science Bulletin, 49(20) :2090-2094 (in Chinese)
[28] Zhang JX, Meng F C and Yang JS. 2005. P-T evolutions for the Yuqia eclogite in the North Qaidam Mountains. Acta Petrologica et Mineralogica, 24 : 245 - 254 ( in Chinese with English abstract)
[29] Zhang JX, Yang JS, Mattinson CG, Xu ZQ, Meng FC and Shi RD. 2005. Two contrasting eclogite cooling histories, North Qaidam HP/ UHP terrane, western China: Petrological and isotopic constraints. Lithos, 84 : 51 - 76
[30] Zhang JX, Meng FC, Yu SY and Qi XX. 2007. Metamorphic history recorded in high pressure mafic granulites in the Luliangshan Moutains to the north of Qaidam Basin, northwest China: Evidence from petrology and zircon SHRIMP geochronology. Earth Science Frontiers, 14( 1 ) : 85 -97( in Chinese with English abstract)
[31] Zhang JX, Mattinson CG, Meng FC, Wan YS and Tung K. 2008. Polyphase tectonothermal history recorded in granulitized gneisses from the north Qaidam HP/UHP metamorphic terrane, western China: Evidence from zircon U-Pb geochronology. GSA Bulletin, 120(5 -6) : 732 -749
[32] 侯振辉,李曙光,陈能松,李秋立,柳小明.2005.大别造山带惠兰山镁铁质麻粒岩Sm-Nd和锆石SHRIMP U-Pb年代学及锆石微量元素地球化学.中国科学(D辑),35(12):1103-1111
-
计量
- 文章访问数: 7397
- PDF下载数: 7607
- 施引文献: 0
下载: