
西藏措勤地区敌布错组时代重新厘定
刘函, 李俊, 高睿, 苟正彬, 张士贞
西藏措勤地区敌布错组时代重新厘定
The Age Re-Determination of the Dibucuo Formation in Cuoqin Area, Xizang
措勤地区上二叠统敌布错组与区域上古生物及地层研究进展存在矛盾,需要加强对其时代的厘定以准确理解其地质意义.基于锆石U-Pb定年,并结合野外调查与区域地层对比,将敌布错组重新归并为3类时代不同的岩石地层单元.敌布错组A以含砾砂板岩及晚古生代植物化石为特征,碎屑锆石年龄谱与拉嘎组类似,为拉嘎组或者昂杰组.敌布错组B为海陆交互相碎屑岩,获得系列早白垩世早期年龄值,结合被早白垩世岩体侵位的特征将其厘定为则弄群下部.敌布错组C完全由早白垩世晚期火山岩与火山碎屑岩组成,与则弄群上部一致.结合区域资料,认为措勤地区中二叠世‒晚三叠世为连续的碳酸盐岩沉积,没有受到晚古生代岛弧造山作用的影响,早白垩世班公湖‒怒江残余海盆的南界在措勤地区较之前的认识向南推进了约50 km.
The Upper Permian Dibucuo Formation in Cuoqin area is subject to age redetermination to accurately understand its geological significance since it is contradicted by the research progress of regional paleontology and stratigraphy. Based on field survey, regional stratigraphic correlation and detrital zircons U-Pb dating, the Dibucuo Formation is reclassified into three lithostratigraphic units of different ages. The Dibucuo Formation A is characterized by conglomerate-bearing sand-slate and Late Paleozoic plant fossils, and similar clastic zircons age spectrum with the Laga Formation, which should be classified into Laga Formation or Angjie Formation. Dibucuo Formation B is mainly composed of marine-continental clastic rocks, which is determined as the lower part of the Lower Cretaceous Zenong Group according to the Early Cretaceous clastic zircons and its emplacement by Early Cretaceous intrusive rocks. Dibucuo Formation C is almost completely composed of the late Early Cretaceous volcanic and pyroclastic rocks, consistent with the upper part of the Lower Cretaceous Zenong Group. Combined with the regional data, it is believed that the Cuoqin area was a continuous carbonate deposit from the Middle Permian to the Late Triassic, which was not affected by the Late Paleozoic Gangdese island arc orogenesis. The Early Cretaceous southern boundary of Bangongco-Nujiang residual sea basin in Cuoqin area is pushed about 50 km southward compared with the previous understanding.
冈底斯 / 敌布错组 / 晚二叠世 / 早白垩世 / 措勤 / 地层学 / 岩石学.
Gangdese / Dibucuo Formation / Late Permian / Early Cretaceous / Cuoqin / stratigrapgy / petrology
P535
Chen, Q. H., Wang, J. P., Wang, S. L., et al., 1998. Discovery of the Upper Permian and Its Geological Significance in the Cuoqin Basin, Tibet. Chinese Science Bulletin, 43(19): 2111-2114 (in Chinese).
|
Chen, S. S., Shi, R. D., Gong, X. H., et al., 2017. A Syn-Collisional Model for Early Cretaceous Magmatism in the Northern and Central Lhasa Subterranes. Gondwana Research, 41: 93-109. https://doi.org/10.1016/j.gr.2015.04.008
|
Cui, H. J., Gou, Z. B., Liu, H., et al., 2019. The Petrogenesis and Tectonic Significance of the Late Early Cretaceous Granodiorites in the Nyixung Area, Western Lhasa Block, Xizang. Sedimentary Geology and Tethyan Geology, 39(1): 1-13 (in Chinese with English abstract).
|
Du, F. J., Lu, S. W., Gao, L. D., et al., 2006. Characteristics and Significance of Late Permian Sporopollen Assemblage in Gongjiubu Area, Angren County, Southern Tibet. Geological Bulletin of China, 25(S1): 168-172 (in Chinese with English abstract).
|
Duan, M. L., Xie, C. M., Wang, B., et al., 2022. Ocean Island Rock Assembly and Its Tectonic Significance in Tangga-Sumdo Area, Tibet. Earth Science, 47(8): 2968-2984 (in Chinese with English abstract).
|
Gao, S. B., Zheng, Y. Y., Tian, K., et al., 2021. Geochronology of Magmatic Intrusions and Mineralization of Lunggar Iron Deposit in Tibet and Its Implications for Regional Multi-Stage Iron Mineralization: Geochemistry, Zircon U-Pb and Phlogopite Ar-Ar Isotopic Dating Constraints. Earth Science, 46(6): 1941-1959 (in Chinese with English abstract).
|
Geng, Q. R., Zhang, Z., Peng, Z. M., et al., 2020. Petrogeochemistry and Metallogenesis Related to Xiongmei-Baingoin Granitic Zone in Central Tibet. Earth Science, 45(8): 2805-2825 (in Chinese with English abstract).
|
Gou, Z. B., Liu, H., Li, J., et al., 2018. The Petrogenesis and Tectonic Significance of Early Cretaceous Volcanic Rocks in Nixiong Area from the Central and Northern Lhasa Terrane. Earth Science, 43(8): 2780-2794 (in Chinese with English abstract).
|
Guo, L., Zhang, H. F., Harris, N., et al., 2016. Late Devonian-Early Carboniferous Magmatism in the Lhasa Terrane and Its Tectonic Implications: Evidences from Detrital Zircons in the Nyingchi Complex. Lithos, 245: 47-59. https://doi.org/10.1016/j.lithos.2015.06.018
|
Huang, T. T., Xu, J. F., Chen, J. L., et al., 2017. Sedimentary Record of Jurassic Northward Subduction of the Bangong-Nujiang Ocean: Insights from Detrital Zircons. International Geology Review, 59(2): 166-184. https://doi.org/10.1080/00206814.2016.1218801
|
Ji, W. Q., Wu, F. Y., Zhong, S. L., et al., 2009. Geochronology and Petrogenesis of Granitic Rocks in Gangdese Batholith, Southern Tibet. Science in China (Serise D), 39(7): 849-871 (in Chinese).
|
Ji, Z. S., Yao, J. X., Wu, G. C., 2007. Revision of the Age of the Xiagangjiang Flora and Its Related Strata in the Gêrzê Area, Northern Tibet, China. Geological Bulletin of China, 26(8): 953-959 (in Chinese with English abstract).
|
Ji, Z. S., Yao, J. X., Wu, G. C., et al., 2018. Stratigraphic Progress of the Coqen Basin and Redefinition of the Upper Permian-Jurassic Stratigraphic Sequence. Acta Geoscientica Sinica, 39(4): 401-407 (in Chinese with English abstract).
|
Kang, Z.Q., Xu, J.F., Dong, Y.H., et al., 2008. Cretaceous Volcanic Rocks of Zenong Group in North-Middle Lhasa Block: Products of Southward Subducting of the Slainajap Ocean? Acta Petrologica Sinica, 24(2): 303-314 (in Chinese with English abstract).
|
Li, F. Q., Zhang, S. Z., Li, J., et al., 2022. Definition of Mid-Late Jurassic Peripheral Foreland Basin in the Northern Margin of Lhasa Block. Earth Science, 47(2): 387-404 (in Chinese with English abstract).
|
Li, S., Yin, C. Q., Ding, L., et al., 2020. Provenance of Lower Cretaceous Sedimentary Rocks in the Northern Margin of the Lhasa Terrane, Tibet: Implications for the Timing of the Lhasa-Qiangtang Collision. Journal of Asian Earth Sciences, 190: 104162. https://doi.org/10.1016/j.jseaes.2019.104162
|
Li, X. X., Wu, Y. M., Fu, Z. B., 1985. Preliminary Study on a Mixed Permian Flora from Xiagangjiang of Gerze District, Xizang and Its Palaeobiogeographic Significance. Acta Palaeontologica Sinica, 24(2): 150-170 (in Chinese with English abstract).
|
Li, X. Y., Xie, G. G., Xu, Y. B., et al., 2002. Discovery of the Mid-Late Permian Jianzalong Formation in the Nyixung-Ombu Area in South-Central Tibet Autonomous Region of China. Regional Geology of China, 21(6): 339-344 (in Chinese with English abstract).
|
Liu, H., Li, J., Cui, H. J., et al., 2020. Metallogenic Background and Metallogenic Model of the Early Cretaceous Magnetite Deposit in the Nixiong Area, Tibet. Acta Geologica Sinica, 94(8): 2383-2399 (in Chinese with English abstract).
|
Liu, H., Zhang, L. K., Huang, H. X., et al., 2019. Petrogenesis of Late Triassic Luerma Monzodiorite in Western Gangdise, Tibet, China. Earth Science, 44(7): 2339-2356 (in Chinese with English abstract).
|
Liu, Y. S., Gao, S., Hu, Z. C., et al., 2010. Continental and Oceanic Crust Recycling-Induced Melt-Peridotite Interactions in the Trans-North China Orogen: U-Pb Dating, Hf Isotopes and Trace Elements in Zircons from Mantle Xenoliths. Journal of Petrology, 51(1-2): 537-571. https://doi.org/10.1093/petrology/egp082
|
Ludwig, K. R., 2003. ISOPLOT 3.00: A Geochronological Toolkit for Microsoft Excel. Berkeley Geochronology Center, Berkeley.
|
Mai, Y. J., Zhu, L. D., Yang, W. G., et al., 2021. Zircon U-Pb and Hf Isotopic Composition of Permian Felsic Tuffs in Southeastern Margin of Lhasa, Tibet. Earth Science, 46(11): 3880-3891 (in Chinese with English abstract).
|
Pan, G. T., Mo, X. X., Hou, Z. Q., et al., 2006. Spatial-Temporal Framework of the Gangdese Orogenic Belt and Its Evolution. Acta Petrologica Sinica, 22(3): 521-533 (in Chinese with English abstract).
|
Sun, G. Y., Hu, X. M., Sinclair, H. D., 2017. Early Cretaceous Palaeogeographic Evolution of the Coqen Basin in the Lhasa Terrane, Southern Tibetan Plateau. Palaeogeography, Palaeoclimatology, Palaeoecology, 485: 101-118. https://doi.org/10.1016/j.palaeo.2017.06.006
|
Wang, L. Q., Zhu, D. C., Pan, G. T., 2004. Primary Results and Progress of Regional Geological Survey (1:250000): the South of Qinghai-Tibbet Plateau. Geological Bulletin of China, 23(S1): 413-420 (in Chinese with English abstract).
|
Wang, L. Q., Zhu, T. X., 2013. The Instructions for Geological Map of Qinghai Tibet Plateau and Its Neighbouring Areas (1:1 500 000). Geological Publishing House, Beijing (in Chinese).
|
Wu, G. C., Ji, Z. S., Yao, J. X., et al., 2017. Age Revision of the Dolomite to the West of Namtso and the Significance of the Discovered Oil-Immersed Dolomite. Acta Geologica Sinica, 91(12): 2867-2880 (in Chinese with English abstract).
|
Wu, Y. M., Fu, Z. B., 1986. Carboniferous and Permian Gondwana Facies Strata in Xiagangjiang, Gaize County, Tibet. Journal of Stratigraphy, 10(4): 283-289 (in Chinese with English abstract).
|
Yan, J. J., Zhao, Z. D., Liu, D., et al., 2017. Geochemistry and Petrogenesis of the Late Jurassic Xuru Tso Batholith in Central Lhasa Terrane. Acta Petrologica Sinica, 33(8): 2437-2453 (in Chinese with English abstract).
|
Yang, Y., Liu, H., Cui, H. J., et al., 2019. Evolution of Late Paleozoic Sedimentary Provenance of Lhasa Block: Detrital Zircons from Yongzhu Formation in Cuoqin Area, Tibet. Geological Bulletin of China, 38(6): 1006-1017 (in Chinese with English abstract).
|
Ye, C. L., Huang, B. X., Wang, Y., et al., 2018. Zircon U-Pb Ages of the Late Jurassic Volcanic Rocks from the Zenong Group in the North of Zabuyechaka Area, Tibet and Its Geological Significances. Geological Journal of China Universities, 24(4): 525-535 (in Chinese with English abstract).
|
Zhang, Y.J., An, X.Y., Zhang, Y.C., et al., 2015. The Discovery of Sporopollen Fossiles Bearing Lower Permian Glacio-Marine Sequences of Xainza Area, Tibet. Chinese Science Bulletin, 60(23): 2227-2235 (in Chinese).
|
Zhang, Y. J., Zhu, T. X., Yuan, D. X., et al., 2014. The Discovery of Wuchiapingian Fossils from the Xiala Formation in the Xainza Area (Tibet) and Its Significance. Journal of Stratigraphy, 38(1): 25-32 (in Chinese with English abstract).
|
Zhao, B., Liu, D. Z., Tao, X. F., et al., 2010. New Discovery of Jurassic Strata at Quluo Township, Cuoqin County, Tibet, China. Geological Bulletin of China, 29(11): 1633-1639 (in Chinese with English abstract).
|
Zheng, Y. Y., Xu, R. K., Wang, C. Y., et al., 2007. Discovery of Early Triassic Conodonts on the Western Margin of Gangdese and the Establishment of the Tangnale Formation. Science in China (Serise D), 37(7): 916-921 (in Chinese).
|
Zhou, Y. Y., Jiang, Y. S., Wang, M. G., 2002. Permian Dibuco Formation in the Coqên-Xainza Stratigraphic Area, Tibet. Regional Geology of China, 21(2): 79-82 (in Chinese with English abstract).
|
Zhu, D. C., Mo, X. X., Niu, Y. L., et al., 2009. Geochemical Investigation of Early Cretaceous Igneous Rocks along an East-West Traverse throughout the Central Lhasa Terrane, Tibet. Chemical Geology, 268(3-4): 298-312. https://doi.org/10.1016/j.chemgeo.2009.09.008
|
Zhu, D. C., Zhao, Z. D., Niu, Y., et al., 2011. Lhasa Terrane in Southern Tibet Came from Australia. Geology, 39(8): 727-730. https://doi.org/10.1130/g31895.1
|
Zhu, D. C., Mo, X. X., Zhao, Z. D., et al., 2008. Zircon U-Pb Geochronology of Zenong Group Volcanic Rocks in Coqen Area of the Gangdese, Tibet and Tectonic Significance. Acta Petrologica Sinica, 24(3): 401-412 (in Chinese with English abstract).
|
感谢各位审稿专家对稿件的宝贵意见!本文在成文过程中与王立全研究员进行了有益的讨论,野外工作得到李奋其、杨洋、李泽瑜、张华的帮助!附表见https://doi.org/10.3799/dqkx.2023.086.
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