U-Pb Zircon Dating of the Mesozoic Volcanic Strata in Luanping of North Hebei and Its Significance
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摘要: 在冀北—辽西地区, 冀北的滦平地区是中生代地层最为齐全, 也是唯一的晚中生代沉积作用基本连续的地区.许多研究者认为该地区的土城子组与张家口之间存在着J3—K1界线和中生代的构造转换界面.该地区分布的主要中生代地层自下而上依次为髫髻山组、土城子组、张家口组、大北沟组、大店子组和西瓜园组.通过LAICPMS方法的锆石UPb测年, 获得了该地区中生代火山岩地层的年代格架, 即髫髻山组的顶界年龄为(162.8±3.2)Ma, 土城子组形成的主体年代范围是(142.6±1.3)~(136.4±1.9)Ma, 张家口组形成的年代范围是(135.7±1.8)~(135.2±2.3)Ma, 大店子组顶部安山岩的年龄是(131.4±3.7)~(130.2±3.0)Ma.锆石的稀土元素分析表明: 土城子组中锆石的稀土元素特征与张家口组中锆石的特征一致, 而与髫髻山组中的锆石有较大的区别.综合以上分析数据及野外地质特征可以得出以下结论: (1)该地区的土城子组与髫髻山组之间不仅时间间隔较长, 而且二者中火山岩的源区也有较大的区别; 土城子组与张家口组之间不仅时间上基本连续, 而且二者中火山岩的源区也有明显的一致性.这就表明了滦平地区的土城子组与张家口组是同一地质背景下的产物, 即该地区二者之间应不存在J3—K1界面和构造转换界面.(2)滦平地区大店子组顶部火山岩在年代上与辽西北票—义县地区的义县组底部、辽西凌源地区的张家口组顶部基本相当.Abstract: The Mesozoic strata in Luanping, North Hebei Province are the most complete in North Hebei-West Liaoning, and the Luanping area is the only area where the deposit action in the Late Mesozoic is successive. A lot of researchers think the boundary of the J3-K1 and the tectonic framework transition interface in Mesozoic Era in North Hebei-West Liaoning are located between the Tuchengzi and Zhangiiakou formations in the Luanping area. The Mesozoic strata in Luanping from the lower to the upper are the Tiaojishan Formation, Tuehengzi Formation, Zhangjiakou Formation, Dabeigou Formation, Dadianzi Formation and the Xiguayuan Formation. U-Pb zircon dating of LA-ICP-MS obtained the age frame of the Mesozoic volcanic strata in the Luanping area. The top age of the Tiaojishan Formation is (162.8±3.2)Ma, the main forming period of the Tuehengzi Formation is (142.6±1.3)Ma-(136.4±1.9)Ma, the forming period of the Zhangjiakou Formation is (135.7±1.8)Ma--(135.2±2.3)Ma, and the age of the volcanic rocks in the top of the Dadianzi Formation is (131.4±3. 7)Ma--(130.2±3. 0)Ma. Analysis shows that the rare earth element characteristics of zircons from the Tuehengzi Formation are very similar to those from the Zhangiiakou Formation, but are very different from those from the Tiaojishan Formarion. Combined with the field characteristics of the strata, the following conclusions are drawn: (1) the time interval Detween the Tuchengzi and Tiaojishan formations is longer, and the magmatic sources of the volcanic rocks are very different; the forming period between the Tuchengzi and the Zhangjiakou formations is continuous, and the magmatic sources of the volcanic rocks are very similar. The results imply that the Tuchengzi and Zhangjiakou formations were formed in the same geological background, and so are not the boundary of the J3-K1 and the tectonic framework transition interface between the Tuchengzi and Zhangjiakou formations in the Luanping area. (2) The age of the volcanic rocks in the top of the Dadianzi Formation corresponds to that of the bottom of the Yixian Formation in the Beipiao-Yixian area in West Liaoning Province, and corresponds to that of the top of the Zhangiiakou Formation in Lingyuan, West Liaoning Province.
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图 1 北滦平附近地区地质简图
1.砂岩、粉砂岩；2.砂砾岩；3.凝灰岩；4.凝灰质砂岩；5.中性火山岩及同质角砾；6.酸性火山岩；7.断裂；8.采样点；J2t.髫髻山组；(J—K)t. 土城子组；K1z.张家口组；K1d.大北沟组；K1dd.大店子组；K1x.西瓜园组
Fig. 1. Simplified geological map in Luanping area
图 2 北滦平附近地区的中生代地层柱状关系简图
1.砂岩、粉砂岩；2.砂砾岩；3.凝灰质砂岩；4.凝灰岩；5.中性火山岩及同质角砾；6.酸性火山岩
Fig. 2. Simplified Mesozoic strata column in Luanping area
图 3 滦平火山岩样品中锆石的阴极发光照片(其中的黑色圆圈为激光剥蚀位置)
Fig. 3. CL images of zircons from the Luanping volcanic rocks
图 4 平地区火山岩样品的锆石U-Pb谐和图
Fig. 4. U-Pb concordant diagrams of zircons from volcanic samples in Luanping area
图 5 平地区样品中锆石的稀土元素球粒陨石标准化图解
Fig. 5. Chondrite-normalized REE patterns of zircons from samples in Luanping area
表 1 采样点位置及锆石测年
Table 1. Sample locations and their LA-ICP-MS U-Pb ages of zircons
表 2 样品中错石的LA-ICP-MS U-Pb分析数据
Table 2. U-Pb isotopic data of zircons from samples in Luanping area by LA-ICP-MS
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[1] Andersen, T., 2002. Correlation of common lead in U-Pb an-alyses that do not report 204Pb. Chemical Geology, 192: 59-79. doi: 10.1016/S0009-2541(02)00195-X [2] Chen, P.J., Dong, Z.M., Zhen, S.N., 1998. An exceptionally well-preserved theropod dinosaur from the Yixian For-mation of China. Nature, 391: 147-152. doi: 10.1038/34356 [3] Davis, G.A., Zheng, Y.D., Wang, C., et al., 2001. Mesozoic tectonic evolution of the Yanshan fold and thrust belt, with emphasis on Hebei and Liaoning provinces, north-ern China. In: Hendrix, M.S., Davis, G.A., eds., Pale-ozoic and Mesozoic tectonic evolution of Central Asia: From continental assembly to intracontinental deforma-tion. Geological Society of America Memoir, 194: 171-197. [4] Hancher, J.M., Hoskin, P.W.O., 2003. Zircon. Reviews in Mineralogy and Geochemistry, 53: 26-61. [5] Ji, Q., Currie, P.J., Norell, M., et al., 1998. Two feathered dinosaurs from northeastern China. Nature, 393: 753-761. doi: 10.1038/31635 [6] Ji, Q., Chen, W., Wang, W.L., et al., 2004. Mesozoic Jehol Biota of western Liaoning, China. Geological Publishing House, Beijing, 1-375(in Chinese). [7] Liu, Y.Q., Li, P.X., Tian, S.G., 2003. SHRIMP U-Pb zir-con age of Late Mesozoic tuff(lava)in Luanping basin northern Hebei, and its implications. Acta Petrologica Mineralogica, 22(3): 237-244(in Chinese with English abstract). [8] Niu, B.G., He, Z.J., Song, B., et al., 2003. SHRIMP geo-chronology of volcanics of the Zhangjiakou and its sig-nificance. Geological Bulletin of China, 22(2): 140-141(in Chinese). [9] Niu, B.G., He, Z.J., Song, B., et al., 2004. SHRIMP geo-chronology of volcanics of the Zhangjiakou and Yixian formations, northern Hebei Province, with a discussion on the age of the Xing'anling Group of the Great Hing-gan mountains and volcanic strata of the southeastern coastal area of China. Acta Geologica Sinica (English Edition), 78(6): 1214-1228. doi: 10.1111/j.1755-6724.2004.tb00778.x [10] Niu, S.W., Li, P.X., Tian, S.G., et al., 2002. New research progress of conchostracon fossils from the Dabeigou Formation in the Luanping basin, Hebei, China. Geological Bulletin of China, 21(6): 322-328(in Chinese with English abstract). [11] Ren, J.S., Wang, Z.X., Chen, B.W., et al., 2002. China and adjacent tectonic map(1∶ 5 000 000). Geological Pub-lishing House, Beijing(in Chinese). [12] Swisher, C.C., Wang, X.L., Zhou, Z.H., et al., 2001. New evidence of the Yixian Formation isotopic ages and the dating of the Tuchengzi Formation 40Ar/39 Ar. Chinese Science Bulletin, 46(23): 2009-2013(in Chinese). doi: 10.1007/BF02901918 [13] Sun, G., Dilcher, D.L., Zheng, S.L., et al., 1998. In search of the first flower: A Jurassic angiosperm, Archaefructus, from Northeast China. Science, 282(5394): 1692-1695. doi: 10.1126/science.282.5394.1692 [14] Swisher, C.C., Wang, Y.Q., Wang, X.L., et al., 1999. Cre-taceous age of the feathered dinosaurs of Liaoning, China. Nature, 400: 58-61. doi: 10.1038/21872 [15] Tian, S.G., Pang, Q.Q., Niu, S.W., et al., 2004. Terrestrial Jurassic-Cretaceous boundary stratotype candidate in Luanping, northern Hebei. Geological Bulletin of China, 23(12): 1171-1180(in Chinese with English abstract). [16] Wang, W. L., Zhang, H., Zhang, L. J., et al., 2004. The standard stratigraphic sections of Tuchengzi stage and Yixian stage and their stratigraphy, palaeontology and tectonic-volcanic actions. Geological Publishing House, Beijing, 21-69(in Chinese with English abstract). [17] Xu, X., Zhou, Z.H., Prum, R., 2001. Branched integumental structures in Sinornithosaurus and the origin of feathers. Nature, 410: 200-204. doi: 10.1038/35065589 [18] Yuan, H. L., Gao, S., Liu, X. M., et al., 2004. Accurate U-Pb age and trace element determinations of zircon by laser ablation-inductively coupled plasma mass spec-trometry. Geoanalytical and Geostandard Newsletters, 28(3): 353-370. doi: 10.1111/j.1751-908X.2004.tb00755.x [19] Yuan, H.L., Wu, F.Y., Gao, S., et al., 2003. Determination of U-Pb age and rare earth element concentrations of zircons from Cenozoic intrusions in northeastern China by laser ablation ICP-MS. Chinese Science Bulletin, 48 (22): 2411-2421. [20] Zhang, C.H., Wu, X.G., Xu, D.B., et al., 2004. Mesozoic tectonic framework and evolution in central segment of the introplate Yanshan orogenic belt. Geological Bulletin of China, 23(9-10): 864-875(in Chinese with English abstract). [21] Zhang, H., Liu, X.M., Zhang, Y.Q., et al., 2005a. Zircon U-Pb ages and significance of bottom and top beds of Zhangjiakou Formation in Liaoning and Hebei prov-inces. Earth Science—Journal of China University o f Geosciences, 30(4): 387-401(in Chinese with English abstract). [22] Zhang, H., Liu, X.M., Gao, S., et al., 2005b. Redefination of the Zhangjiakou Formation in Lingyuan, western Liaoning and its significance—Constraints from laser ICP-MS zircon U-Pb ages. Geological Bulletin of China, 24(2): 110-117(in Chinese with English abstract). [23] Zhang, H., Wang, W.L., Li, Z.T., et al., 2004. Comprehen-sive correlation of the Yixian Formation in the Beipiao and Yixian areas, western Liaoning. Geological Bulletin of China, 23(8): 766-777(in Chinese with English abstract). [24] Zhao, Y., Zhang, S. H., Xu, G., et al., 2004. The Jurassic major tectonic event of the Yanshanian introplate de-formation belt. Geological Bulletin of China, 23(9-10): 854-863(in Chinese with English abstract). [25] Zhou, Z.Y., Zheng, S.L., 2003. The missing link in Ginkgo evolution. Nature, 423: 821-822. doi: 10.1038/423821a [26] Zhou, Z., Barrett, P.M., Hilton, J., 2003. An exceptionally preserved Lower Cretaceous ecosystem. Nature, 421: 807-814 doi: 10.1038/nature01420 [27] 季强, 陈文, 王五力, 等, 2004. 中国辽西中生代热河生物群. 北京: 地质出版社, 1-375. [28] 柳永清, 李佩贤, 田树刚, 2003. 冀北滦平晚中生代火山碎屑(熔)岩中锆石SHRIMP U-Pb年龄及其地质意义. 岩石矿物学杂志, 22(3): 237-244. doi: 10.3969/j.issn.1000-6524.2003.03.005 [29] 牛宝贵, 和政军, 宋彪, 等, 2003. 张家口组火山岩SHRIMP定年及其重大意义. 地质通报, 22(2): 140-141. 牛绍武, 李佩贤, 田树刚, 等, 2002. 冀北滦平盆地大北沟组叶肢介化石研究新进展. 地质通报, 21(6): 322-328. https://www.cnki.com.cn/Article/CJFDTOTAL-ZQYD200302009.htm [30] 牛绍武,李佩贤,田树刚,等,2002.冀北滦平盆地大北沟组叶肢介化石研究新进展.地质通报,21(6):322—328. doi: 10.3969/j.issn.1671-2552.2002.06.008 [31] 任纪舜, 王作勋, 陈炳蔚, 等, 2002. 中国及邻区大地构造图(1∶ 5 000 000)及说明书. 北京: 地质出版社. [32] Swisher, C.C., 汪筱林, 周忠和, 等, 2001. 义县组同位素年代新证据及土城子组40 Ar/39 Ar年龄测定. 科学通报, 46 (23): 2009-2013. doi: 10.3321/j.issn:0023-074X.2001.23.019 [33] 田树刚, 庞其清, 牛绍武, 等, 2004. 冀北滦平盆地陆相侏罗系-白垩系界限候选层型剖面初步研究. 地质通报, 23 (12): 1171-1180. https://www.cnki.com.cn/Article/CJFDTOTAL-ZQYD200412001.htm [34] 王五力, 张宏, 张立君, 等, 2004. 土城子阶、义县阶标准地层剖面及其地层古生物、构造—火山作用. 北京: 地质出版社, 21-69. [35] 张长厚, 吴鑫国, 徐德斌, 等, 2004. 燕山板内造山带中段中生代构造格局与构造演化. 地质通报, 23(9-10): 864-875. https://www.cnki.com.cn/Article/CJFDTOTAL-ZQYD2004Z2006.htm [36] 张宏, 柳小明, 张晔卿, 等, 2005a. 冀北滦平—辽西凌源地区张家口组火山岩顶、底的单颗粒锆石U-Pb测年及意义. 地球科学——中国地质大学学报, 30(4): 387-401. https://www.cnki.com.cn/Article/CJFDTOTAL-DQKX200504002.htm [37] 张宏, 柳小明, 高山, 等, 2005b. 辽西凌源地区张家口组的重新厘定及其意义——来自激光ICPMS锆石U-Pb年龄的制约. 地质通报, 24(2): 110-117. https://www.cnki.com.cn/Article/CJFDTOTAL-ZQYD200502003.htm [38] 张宏, 王五力, 李之彤, 等, 2004. 辽西北票和义县地区义县组的综合对比研究. 地质通报, 23(8): 766-777. doi: 10.3969/j.issn.1671-2552.2004.08.007 [39] 赵越, 张拴宏, 徐刚, 等, 2004. 燕山板内变形带侏罗纪主要构造事件. 地质通报, 23(9-10): 854-863. https://www.cnki.com.cn/Article/CJFDTOTAL-ZQYD2004Z2005.htm -
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