西藏冈底斯带措勤地区则弄群火山岩锆石U-Pb年代学格架及构造意义
Zircon U-Pb geochronology of Zenong Group volcanic rocks in Coqen area of the Gangdese, Tibet and tectonic significance
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摘要: 大规模的则弄群火山岩呈带状近东西向展布于西藏冈底斯带中北部地区.对出露状况较好的措勤地区则弄群火山岩进行了锆石U-Pb定年,以建立其年代学格架便于区域对比.措勤地区则弄群火山岩多数锆石具有生长振荡环带,部分锆石显示核边结构.在措勤达雄北西部上覆于中二叠统下拉组灰岩的1件则弄群英安岩样品的LA-ICP-MS锆石U-Ph年龄为130±1Ma,1件则弄群流纹岩样品的SHRIMP锆石U-Pb年龄为129±3Ma;在措勤达雄北东部与下白垩统多尼组碎屑岩呈断层接触的1件则弄群英安岩样品中的锆石具有两组LA-ICP-MS锆石U-Pb年龄,最年轻的一组(包括增生边)为121±1Ma,较老的一组(包括核部)为131±1Ma;在措勤南西部1件则异群流纹岩样品的LA-ICP-MS锆石U-Pb年龄为111±1Ma,与措勤地区花岗岩类的侵位时代相当.这些高质量的锆石U-Pb年代学数据表明,措勤地区的则弄群火山作用很可能开始于约130Ma,停息于约110Ma,持续时间约20Ma.区域对比表明,东西延伸约1000km的则弄群火山作用同时发生在约130Ma.区域上目前的年代学数据结合同时代岩浆作用的分布特征表明,冈底斯带中北部地区早白垩世岩浆作用不太可能由新特提斯洋壳向北的低角度或平板俯冲产生.
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[1] Allmendinger RW, Jordan TE, Kay SM and Isacks BL. 1997, The evolution of the Ahiplano - Puna plateau of the central Andes. Annual Review of Earth and Planetary Sciences, 25: 139- 174
[2] Anderson T. 2002. Correction of common Pb in U-Pb analyses that do not report ^204 Pb. Chemical Geology, 192 : 59 - 79
[3] Chang CF and Zheng XL, 1973. Discussion on the formation of westerneastern ranges in Himalayas and Qinghai-Xizang Plateau and characteristics of geological structure in Everest region. Science in China (Series D), 2:190-201 (in Chinese)
[4] Copeland P, Harrison TM, Pan Y, Kidd WSF, Roden M and Zhang YQ. 1995. Thermal evolution of the Gangdese batholith, southern Tibet: A history of episodic unroofing. Tectonics, 14 : 223 - 236
[5] Coulon C, Maluski H, Bollinger C and Wang S. 1986. Mesozoic and Cenozoic volcanic rocks from central and southern Tibet: ^39Ar/^40Ar dating, petrological characteristics and geodynamical significance. Earth and Planetary Science Letters, 79:281 -302
[6] Ding L and Lai QZ. 2003. New geological evidence of crustal thickening in the Gangdese block prior to the Indo-Aslan collision. Chinese Science Bulletin, 48 ( 15 ) : 1604 - 1610
[7] Ding L, Kapp P, Yin A, Deng WM and Zhong DL. 2003. Early Tertiary volcanism in the Qiangtang terrane of central Tibet: Evidence for a transition from oceanic to continental subduction. Journal of Petrology, 44:1833 - 1865
[8] Gutscher MA, Maury R and Eissen JP. 2000. Can slab melting be caused by flat subduction? Geology, 28 (6) : 535 -538
[9] Harris NBW, Inger S and Xu R. 1990. Cretaceous plutonism in central Tibet: An example of post-collision magmatism? Journal of Volcanology and Geothermal Research, 44 : 21 - 32
[10] He ZH, Yang DM, Zheng CQ and Huang YC. 2005. Geochemistry of the Indosinian granitoids in the Mamba area, Gangdise belt, Tibet and its tectonic significance. Geological Bulletin of China, 24(4): 354-359
[11] He ZH, Yang DM, Zheng CQ and Wang TW. 2006. Isotopic dating of the Mamba granitoid in the Gangdese tectonic belt and its constraint on the subduction time of the Neo-Tethys. Geological Review, 52 ( 1 ) : 100 - 106
[12] Hoskin PWO and Black LP. 2000. Metamorphic zircon formation by solid-state rccrystallization of protolith igneous zircon. Journal of Metamorphic Geology, 18 : 423 -439
[13] Hsu KJ, Pan GT and Sengor AMC. 1995. Tectonic evolution of the Tibetan Plateau: A working hypothesis based on the archipelago model of orogenesis. International Geology Review, 37 : 473 - 508
[14] Kapp P, DeCelles PG, Gehrels GE, Heizler M and Ding L. 2007. Geological records of the Lhasa-Qiangtang and Indo-Asian collisions in the Nima area of central Tibet. Geological Society of America Bulletin, 119:917 -932, doi: 10. 1130/B26033.1
[15] Kapp P, Murphy MA, Yin A, Harrison TM, Ding L and Guo JR. 2003. Mesozoic and Cenozoic tectonic evolution of the Shiquanhe area of western Tibet. Tectonics, 22 ( 4 ): 1029, doi: 10. 1029/2001TC001332
[16] Kapp P, Yin A, Harrison TM, Ding L. 2005. Cretaceous-Tertiary shortening, basin development, and volcanism in central Tibet. Geological Society of America Bulletin, 117 ( 7/8 ) : 865 - 878
[17] Leier AL, Kapp P, DeCelles PG, Kapp P and Gehrels GE. 2007. Lower Cretaceous strata in the Lhasa tcrrane, Tibet, with implications for understanding the early tectonic history of the Tibetan plateau. Journal of Sedimentary Research, 77 : 809 - 825
[18] Li C, Wang TW, Li HM and Zeng QG. 2003. Discovery of Indosinian megaporphyritic granodiorite in the Gangdcsc area: evidence for the existence of Paleo-Gangdese. Geological Bulletin of China, 22 (5) : 364 - 366
[19] Ludwig KR. 2003. Isoplot/Ex version 3.00. A Geochronological Toolkit for Microsoft Excel. Berkeley: Berkeley Geochronology, Center Special Publication, 4 : 1 - 70
[20] Mo XX, Dong GC, Zhao ZD, Zhou S, Wang LL, Qiu RZ and Zhang FQ. 2005. Spatial and Temporal Distribution and Characteristics of Granitoids in the Gangdese, Tibet and Implication for Crustal Growth and Evolution. Geological Journal of China Universities, 11 (3) : 281 -290
[21] Mo XX, Zhao ZD, Deng JF, Luo ZH, Yu XH, Guo TY, Zhou S and Dong GC. 2004. Mesozoic-Cenozoic igneous rocks in Tibetan Plateau as lithoprobe to the lithosphere. In: Progress in Seismology and Physics of the Earth Interior in China ( Chen YT. Teng JW, Kan RJ and Wang CY) (eds). Beijing: Seismologic Press. 449 -461
[22] Pan GT, Chen ZL, Li XZ, Yang YJ, Xu XS, Xu Q, Jiang XS, Wu YL, Luo JN, Zhu TX and Peng YM. 1997. Geological-tectonic evolution in the eastern Tethys. Beijing: Geological Publishing House, 1997
[23] Pan GT, Mo XX, Hou ZQ, Zhu DC, Wang LQ, Li GM, Zhao ZD, Geng QR and Liao ZL. 2006. Spatial-temporal framework of the Gangdese Orogenic Belt and its evolution. Acta Petrologica Sinica, 22 ( 3 ) : 521 -533
[24] Pan GT, Wang LQ and Zhu DC. 2004. Thoughts on some important seientifie problems in regional geological survey of the Qinghai-Tibet Plateau. Geological Bulletin of China, 23 ( 1 ) : 12 - 19
[25] Pan GT, Zheng HX and Xu YR. 1983. A preliminary study on Bangong Tso-Nujiang Suture. In: Geological memoirs of Qinghai-Xizang Plateau (12) ( Editing committee of geological memoirs of Qinghai-Xizang) (eds). Beijing: Geological Publishing House, 229- 242
[26] Pearce JA and Mei H. 1988. Volcanic rocks of the 1985 Tibet Geotraverse Lhasa to Golmud. Royal Society of London Philosophical Transactions, Series A, 327:169-201
[27] Song B, Zhang YH, Wan YS and Jian P. 2002. Mount making and procedure of the SHRIMP dating. Geological Review, 48 ( sup. ) : 26 -30
[28] Xu RH, Scharer U and Allegre CJ. 1985. Magmatism and metamorphism in the Lhasa block (Tibet) : A geochronological study. Journal of Geology, 93 : 41 - 57
[29] Yuan HL, Gao S, Liu XM, Li HM, Gunther D and Wu FY. 2004. Accurate U-Pb age and trace element determinations of zircon by laser ablation-inductlvely coupled plasma-mass spectrometry. Geostandards and Geoanalytical Research, 28 ( 3 ) : 353 - 370
[30] Zhal QG, Li C, Li HM and Wang TW. 2005. U-Pb zircon age of leucogranite in the central Gangdise, Tibet, and its geological significance. Geological Bulletin of China, 24 ( 3 ) : 349 - 353
[31] Zhang KJ, Xia BD, Wang GM, Li YT, Ye HF. 2004. Early Cretaceous stratigraphy, depositional environments, sandstone provenance, and tectonic setting of central Tibet. Geological Society of America Bulletin, 116:1202-1222, doi: 10. 1130/B25388.1
[32] Zhou CY, Zhu DC, Zhao ZD, Xu JF, Wang LQ, Chen HH, Xie LW, Dong GC and Zhou S. 2008. Petrogenesis of Daxiong pluton in western Gangdese, Tibet: zircon U-Pb dating and Hf isotopic constraints. Acta Petrologica Sinica, 24(2) :348 -358
[33] Zhou YS, Zhang Q and Mei HJ. 1981. Magmatic activities and metamorphisms in Tibet. Beijing: Science Press, 1 - 146
[34] Zhu DC, Pan GT, Chung SL, Mo XX, Zhao ZD, Liao ZL, Wang LQ, Li GM and Dong GC. 2008a. SHRIMP zircon age and geochemical constraints on the origin of Early Jurassic volcanic rocks from the Yeba Formation, southern Gangdese in south Tibet. International Geology Review, 49: 50:442 -471
[35] Zhu DC, Pan GT, Mo XX, Wang LQ, Liao ZL, Zhao ZD, Dong GC and Zhou CY. 2006. Late Jurassic Early Cretaceous geodynamic setting in middle northern Gangdese: new insights from volcanic rocks. Acta Petrologica Sinica, 22 (3): 534- 546
[36] Zhu DC, Pan GT, Wang LQ, Mo XX, Zhao ZD, Zhou CY, Liao ZL, Dong GC and Yuan SH. 2008. Spatial and Temporal variations of the Mesozoic magmatic rocks in the Gangdese Belt, Tibet and discussion on geodynamic setting-related issues involved in their generation. Geological Bulletin of China, 27 (9) : ( in press)
[37] Zhu DC, Pan GT, Zhao ZD, Lee HY, Kaug ZQ, Liao ZL, Wang LQ, Li GM and Dong GC. 2008b. Early Cretaceous subduction-related adakite-like rocks in the Gangdese, south Tibet: products of slab melting and subsequent melt-peridotite interaction? Journal of Asian Earth Sciences, (in revision)
[38] 刘登忠 陶晓风 马润则 石和 朱利东 胡新伟.中华人民共和国1:25万区域地质调查报告措勤县幅[R].,2003.
[39] 谢国剐 邹爱建 袁建芽 廖思平 李晓勇 唐峰林 徐祖丰 陈振华 罗小川 徐银保 肖业斌 曹圣华 黄传冠.中华人民共和国1:25万区域地质调查报告邦多区幅[Z].,2003.
[40] 王天武 程立人 李才 等.中华人民共和国1:25万区域地质调查报告申扎县幅[Z].,2003.
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