Geological Significance of Detrital Zircon U-Pb Age of Middle Devonian Proximal Sedimentary Rocks in Boyang Town, Western Qinling Orogenic Belt
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摘要: 西秦岭伯阳地区中泥盆统砾岩及其砂岩夹层的岩石学特征显示,其成分成熟度和结构成熟度都很低,具有近源沉积岩的特点,砾岩中还含有少量的糜棱岩砾石。砂岩夹层的碎屑锆石具有岩浆锆石的特征,采用LA-ICP-MS锆石U-Pb同位素定年方法,测得碎屑锆石的U-Pb年龄谱明显分为4组:①440~480Ma,约占3%;②540~600Ma,约占4%;③880~1 020Ma,约占79%;④1 040~1 080Ma,约占13%。880~1 020Ma的年龄呈现最强烈的峰值,该年龄峰值与西秦岭地区新元古代晋宁期岩浆作用的时代一致,也与北秦岭地区Rodinia超大陆的汇聚事件一致。结合区域地质资料综合分析,认为研究区在中泥盆世时发生过显著的构造隆升与剥蚀事件。此外,伯阳中泥盆统碎屑沉积物质主要来源于西秦岭和北祁连,说明中泥盆世时研究区与西秦岭造山带之间可能已不存在沉积阻隔区,二者可能已经对接。
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关键词:
- 西秦岭-祁连结合区 /
- 中泥盆统 /
- 碎屑锆石 /
- LA-ICP-MS年代学
Abstract: The petrological study of Middle Devonian sandstones and conglomerates in Boyang area, Western Qinlingorogenic belt indicates that their composition maturity and structure maturity are very low, with the characteristics of the proximal deposit. In addition, the conglomerate has a few of the mylonitic gravels. The clastic zircons of sandstone interbeds from the Middle Devonian conglomerate in Boyang area are characterized by magmatic zircons. By clastic zircon LA-ICP-MS U-Pb dating of the sandstone interbeds, the age spectra of clastic zircon can be divided into 4 groups:①440~480 Ma, accounting for about 3%; ②540~600 Ma, accounting for about 4%; ③880~1 020 Ma, accounting for about 79%; ④1 040~1 080 Ma, accounting for about 13%. The age of 880~1 020 Ma shows the strongest peak, which is in accordance with the age of the Jinning period of Neo-proterozoicmagmatism in the Western Qinlingorogenic belt, and also is in accordance with age of the Rodinia supercontinent aggregation event. Integrating with the regional geological material, it is proposed that a significant tectonic uplift-erosion existed in the studied area during Middle Devonian. The clastic sediments of Middle Devonian strata mainly came from both of the Western Qinling and the Northern Qilian orogenic belt, so it is deduced that no longer exists deposition barrier zone in the area between the studied area and the Western Qinlingorogenic belt during Middle Devonian, and both of the Qinling and Qilian orogenic belts were possibly really amalgamated. -
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杜远生.西秦岭造山带泥盆纪沉积地质学和动力沉积学:西秦岭北带泥盆纪前陆盆地的沉积特征及盆地格局[J].岩相古地理, 1995, 15(4):47-62. DU Yuansheng. Sedimentary geology and dynamic sedimentology of the Devonian strata in the West Qinling Orogenic Belt:sedimentary characteristics and framework of the Devonian foreland basin in the northern belt of the West Qinling Orogenic Belt[J].Sedimentary Facies and Palaeogeography, 1995, 15(4):47-62.
闫臻,王宗起,王涛,等.西秦岭大草滩群的沉积环境及构造意义[J].地质通报, 2002, 21(8-9):505-515. YAN Zhen, WANG Zongqi, WANG Tao, et al. Sedimentary environment and tectonic significance of the Western Qinling Mountains[J].Geological Bulletin of China,2002,21(8-9):505-515.
闫臻,王宗起,王涛,等.秦岭造山带泥盆系形成构造环境:来自碎屑岩组成和地球化学方面的约束[J].岩石学报, 2007, 23(5):1023-1042. YAN Zhen,WANG Zongqi,WANG Tao, et al. Tectonic setting of Devonian sediments in the Qinling Orogen:Cinstraints from detrital modes and geochemistry of clastic rocks[J].Acta Petrologica Sinica, 2007, 23(5):1023-1042.
徐静刚,董云鹏,马海勇,等.天水上泥盆统变砂岩地球化学特征及构造环境[J].西北大学学报(自然科学版), 2006, 36(3):432-436. XU Jinggang,DONG Yunpeng,MA Haiyong, et al. Geochemistry and tectonic setting of the Upper Devonian meta-sandstones from the Tianshui Area[J].Journal of Northwest University(Natural Science Edition), 2006, 36(3):432-436.
朱伟元.甘肃西秦岭北部海相泥盆系研究新进展及西汉水群的再分[J].甘肃地质, 1989, 00:16-28. ZHU Weiyuan. A new advance of the research on marine Devonian stratigraphy in the north part of the West Qinling Mountains of Gansu and the redivision of the Xihanshui Group[J].Gansu Geology, 1989, 00:16-28.
裴先治,丁仨平,李佐臣,等.西秦岭北缘早古生代天水-武山构造带及其构造演化[J].地质学报,2009,83(11):1547-1564. PEI Xianzhi,DING Saping,LI Zuochen, et al. Early Paleozoic Tianshui-Wushan Tectonic zone of the Northern Margin of West Qinling and its Tectonic Evolution[J]. Acta Geologica Sinica, 2009,83(11):1547-1564.
丁守卓,罗金海,程佳孝,等.西秦岭伯阳石英正长斑岩的地球化学、年代学及其地质意义[J].地学前缘, 2015, 22(4):247-254. DING Shouzhuo,LUO Jinhai,CHENG Jiaxiao, et al. Geochemistry and chronology of quartz rothophyre in Boyang of the West Qinling Orogenic Belt,and their geological significance[J].Earth Science Frontiers, 2015, 22(4):247-254.
丁仨平,裴先治,李勇,等.西秦岭北缘新阳-元龙韧性剪切带中花岗质糜棱岩黑云母40Ar-39Ar年龄及地质意义[J].地质学报, 2009, 83(11):1624-1632. DING Saping,PEI Xianzhi,LI Yong, et al. Biotite 40Ar-39Ar ages of Granitic Mylonite at the Xinyang-Yuanlong ductile shear zone in the north margin of West Qinling and their geological significance[J]. Acta Geologica Sinica, 2009, 83(11):1624-1632.
魏博,裴先治,刘成军,等.西秦岭天水地区新阳-元龙韧性剪切带构造变形特征及其地质意义[J].中国地质, 2015, 42(1):51-70. WEI Bo,PEI Xianzhi,LIU Chengjun,et al. Structural deformation of Xinyang-Yuanlong ductile shear zone in Tianshui area,Western Qinling Mountains,and its geological significance[J].Geology in China, 2015, 42(1):51-70.
刘会彬,裴先治,丁仨平,等.西秦岭天水市元龙地区新元古代花岗质片麻岩锆石LA-ICP-MS U-Pb定年及其地质意义[J].地质通报, 2006,25(11):1315-1320. LIU Huishan,PEI Xianzhi,DING Saping,et al. LA-ICP-MS zircon U-Pb dating of the Neoproterozoic granitic gneisses in the Yuanlong area,Tianshui City,West Qinling,China,and their geological significance[J]. Geological Bulletin of China, 2006, 25(11):1315-1320.
裴先治,丁仨平,张国伟,等.西秦岭北缘新元古代花岗质片麻岩的LA-ICP-MS锆石U-Pb年龄及其地质意义[J].地质学报, 2007a, 81(6):772-786. PEI Xianzhi,DING Saping,ZHANG Guowei,et al. Zircons LA-ICP-MS U-Pb dating of Neoproterozoic granitoid gneisses in the north margin of West Qinling and geological implication[J]. Acta Geologica Sinica, 2007a, 81(6):772-786.
刘成军,裴先治,李佐臣,等.西秦岭北缘天水地区新元古代花岗质片麻岩地球化学特征及其形成环境[J].地质通报, 2012, 31(10):1588-1601. LIU Chengjun,PEI Xianzhi,LI Zuochen, et al. Geochemical features and tectonic setting of the Neoproterozoic granitic gneiss in Tianshui area on the northern margin of West Qinling[J].Geological Bulletin of China, 2012, 31(10):1588-1601.
万渝生,许志琴,杨经绥,等.祁连造山带及邻区前寒武纪深变质基底的时代和组成[J].地球学报, 2003, 24(4):319-324. WAN Yusheng,XU Zhiqin,YANG Jingsui, et al. The precambrian high-grade basement of the Qilian terrane and neighboring areas:it's ages and compositions[J].Acta Geoscientica Sinica, 2003, 24(4):319-324.
郭进京,赵凤清,李怀坤.中祁连东段晋宁期碰撞型花岗岩及其地质意义[J].地球学报, 1999, 20(1):10-15. GUO Jinjing,ZHAO Fengqing,LI Huaiqing.Jinningian collisional granite belt in the eastern sector of the central Qilian massif and its implication[J]. Acta Geoscientia Sinica,1999, 20(1):10-15.
张国伟,郭安林,姚安平.中国大陆构造中的西秦岭-松潘大陆构造结[J].地学前缘, 2004, 11(3):23-32. ZHANG Guowei, GUO Anlin, YAO Anping. Western Qinling-Songpan continental tectonic node in China's continental tectonics[J]. Earth Science Frontiers,2004, 11(3):23-32.
徐学义,王洪亮,陈隽璐,等.中祁连东段兴隆山群基性火山岩锆石U-Pb定年及岩石成因研究[J].岩石学报, 2008, 24(4):827-840. XU Xueyi,WANG Hongliang,CHEN Junlu, et al. Zircons U-Pb dating and petrogenesis of Xinglongshan Group basic volcanic rocks at eastern segment of Middle Qilian Mts[J].Acta Petrologica Sinica, 2008, 24(4):827-840.
王金荣.北祁连造山带东段早古生代构造岩浆作用及成矿的研究[D].兰州:兰州大学,2006. WANG Jinrong. Early Paleaozoic tectono-magmatism and mineralization of the eastern section in the North Qilian Orogenic Belt[D].Lanzhou University, 2006.
高景民,裴先治,李佐臣,等.西秦岭天水地区流水沟岩浆杂岩LA-ICP-MS锆石U-Pb测年和岩石地球化学特征[J].地质通报, 2012, 31(9):1482-1495. GAO Jingmin,PEI Xianzhi,LI Zuochen, et al. LA-ICP-MS zircon U-Pb dating and geochemical characteristics of the Liushuigou igneous complex,Tianshui area,West Qinling Mountains[J].Geological Bulletin of China,2012, 31(9):1482-1495.
何世平,王洪亮,陈隽璐,等.北祁连东端陇山岩群斜长角闪岩锆石LA-ICP-MS测年及其地质意义[J].地质学报, 2006, 80(11):1668-1675. HE Shiping,WANG Hongliang,CHEN Junlu, et al. Zircon U-Pb chronology of Longshan Rock Group by LA-ICP-MS and its geological significance[J]. Acta Geologica Sinica,2006, 80(11):1668-1675.
陈隽璐,徐学义,王洪亮,等.北秦岭西段唐藏石英闪长岩岩体的形成时代及其地质意义[J].现代地质, 2008, 22(1):46-51. CHEN Junlu,XU Xueyi,WANG Hongliang, et al. LA-ICP-MS zircon U-Pb dating of Tangzang Quartz-Diorite pluton in the west segment of North Qinling Mountains and its tectonic significance[J].Geoscience,2008, 22(1):46-51.
丁仨平.西秦岭-祁连造山带(东段)交接部位早古生代构造格架及构造演化[D].长安大学,2008. DING Saping. Early Palaeozoic tectonic framework and evolution in the junction of Western Qinling Orogenic Belt and Qilian Orogenic Belt[D]. Chang'an University, 2008.
王婧,张宏飞,徐旺春,等.西秦岭党川地区花岗岩的成因及其构造意义[J].地球科学(中国地质大学学报), 2008, 33(4):474-486. WANG Jing,ZHANG Hongfei,XU Wangchun, et al. Petrogenesis of granites from Dangchuan area in West Qinling Orogenic Belt and its tectonic implication[J].Earth Science-Journal of China University of Geosciences,2008, 33(4):474-486.
吴才来,姚尚志,杨经绥,等.北祁连洋早古生代双向俯冲的花岗岩证据[J].中国地质, 2006, 33(6):1198-1208. WU Cailai,YAO Shangzhi,YANG Jingsui, et al. Double subduction of the Early Paleozoic North Qilian oceanic plate:evidence from granites in the central segment of North Qilian,NW China[J].Geology in China,2006, 33(6):1198-1208.
何世平,王洪亮,徐学义,等.北祁连东段红土堡基性火山岩锆石LA-ICP-MS U-Pb年代学及其地质意义[J].地球科学进展, 2007, 22(2):143-151. HE Shiping,WANG Hongliang,XU Xueyi, et al.A LA-ICP-MS U-Pb chronological study of zircons from Hongtubu basic volcanic rocks and its geological significance in the east segment of North Qilian Orogenic Belt[J].Advances in Earth Science,2007,22(2):143-151.
李王晔.西秦岭-东昆仑造山带蛇绿岩及岛弧型岩浆岩的年代学和地球化学研究-对特提斯洋演化的制约[D].安徽:中国科学技术大学, 2008. LI Wangye. Geochronology and Geochemistry of the ophiolites and island-arc-type igneous rocks in the Western Qinling Orogen and Eastern Kunlun Orogen:implication for the evolution of the Tethyan Ocean[D].University of Science and Technology of China,2008.
陈隽璐,李好斌,王洪亮,等.秦祁结合部位王家岔石英闪长岩体锆石LA-ICP-MS定年及地质意义[J].吉林大学学报(地球科学版), 2007, 37(3):423-431. CHEN Junlu,LI Haobin,WANG Hongliang, et al. LA-ICP-MS zircon U-Pb dating of a quartz diorite pluton from Wangjiacha,the junction area between the Qinling and Qilian Orogenic Belts and its tectonic significance[J].Journal of Jilin University(Earth Science Edituon),2007,37(3):423-431.
陈隽璐,何世平,王洪亮,等.秦岭祁连造山带接合部位基性岩墙的LA-ICP-MS锆石U-Pb 年龄及其地质意义[J].岩石矿物学杂志, 2006, 25(6):456-462. CHEN Junlu,HE Shiping,WANG Hongliang, et al. Zircon LA-ICP-MS U-Pb age of mafic dykes in the area between the Qinling and the Qilian Orogenic Belts and its geological implications[J]. Acta Petrologica Et Mineralogica,2006,25(6):456-462.
何艳红,陈亮,孙勇,等.陇县地区新街片麻岩套锆石年龄及其地质意义[J].西北大学学报(自然科学版), 2005, 35(5):625-627. HE Yanhong,CHEN Liang,SUN Yong, et al. Zircon chronology of Xinjie complex in Longxian County and its geological significance[J].Journal of Northwest University(Natural Science Edition),2005,35(5):625-627.
魏方辉,裴先治,李瑞保,等.甘肃天水地区早古生代黄门川花岗闪长岩体LA-ICP-MS锆石U-Pb定年及构造意义[J].地质通报, 2012, 31(9):1496-1509. WEI Fanghui,PEI Xianzhi,LI Ruibao, et al. LA-ICP-MS zircon U-Pb dating of early Paleozoic Huangmenchuan granodiorite in Tianshui area of Gansu Province and its tectonic significance[J].Geological Bulletin of China,2012, 31(9):1496-1509.
裴先治,孙仁奇,丁仨平,等.陇东地区阎家店闪长岩LA-ICP-MS锆石U-Pb测年及其地质意义[J].中国地质, 2007b, 34(1):8-16. PEI Xianzhi,SUN Renqi,DING Saping, et al. LA-ICP-MS zircon U-Pb dating of the Yanjiadian diorite in the eastern Qilian Mountains and its geological significance[J].Geology in China, 2007b,34(1):8-16.
LERCH M F, XUE F, KRONER A, et al. A middle Silurian-early Devonian magmatic are in the Qinling mountains of central China[J]. Journal of Geology, 1995, 103:437-449.
HOSKION P W O. Rare earth element chemistry of zircon and its use as a provenance indicator[J]. Geology, 2002, 28(8):627-630.
BELOUSOVA E A, GRIFFIN W L, O'RILLY S Y. Igneous zircon:trace element composition as an indicator of source rock type[J]. Contrib. Mineral. Petrol., 2002, 143:602-622.
VAVRA G, SCHMID R, GEBAUER D. Internal morphology, habit and U-Th-Pb microanalysis of amphibole to granulite facies zircon:Geochronology of the Ivren Zone (Southern Alps)[J]. Contrib Mineral Petrol, 1999, 134:380-404.
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 superplume that broke up Rodinia[J]. Precambrian Res. 2003, 122(1-4):85-109.
LING W L, GAO S, ZHANG B R, et al. Neoproterozoic tectonic evolution of the northwestern Yangtze craton, South China:implications for amalgamation and break-up of the Rodinia Supercontinent[J]. Precambrian Res. 2003, 122(1-4):111-140.
ZHENG Y F. Neoproterozoic magmatic activity and global change[J]. Chinese Science Bulletin, 2003, 48(16):1639-1656.
ZHANG H F, ZHANG B R, HARRIS N, et al. U-Pb zircon SHRIMP ages,geochemical and Sr-Nd-Pb isotopic compositions of intrusive rocks from the Longshan-Tianshui area in the southeast corner of the Qilian Orogenic Belt,China:Constraints on petrogenesis and tectonic affinity[J].Journal of Asian Earth Sciences, 2006, 27:751-764.
EVA E, AMY W, LOTHAR R, et al. How was the Triassic Songpan-Ganzi basin filled-A provenance study[J]. Tectonics, 2007, 26:1-24.
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