鄂西走马地区大塘坡组顶部泥岩碎屑锆石LA-ICP-MS U-Pb年龄及其地质意义
|
摘要
地球在新元古代经历了Rodinia超大陆的聚合和解体,并发生了Sturtian和Marinoan两期全球规模的冰川事件。华南地区南华系古城组和南沱组冰碛岩分别对应Sturtian冰期和Marinoan冰期沉积记录,大塘坡组属于其间冰期沉积。对鄂西走马地区大塘坡组顶部泥岩中的碎屑锆石进行了LA-ICP-MS U-Pb定年,锆石具有高Th/U比值(0.47～1.69),并显示明显的振荡环带,为岩浆成因;62颗锆石的62个数据点分析,获得的60个谐和年龄分布在651～2435Ma,主要峰值为～794Ma。最年轻单颗锆石U-Pb年龄651±7.7Ma,结合前人研究认为华南地区Marinoan冰期启动时间应晚于651Ma;碎屑锆石为亲扬子型,可能来自鄂中古陆和扬子北缘;分布最集中的751～851Ma年龄段内～850Ma峰值记录了扬子地台与华夏褶皱带碰撞拼合事件,而～820Ma、～800Ma、～760Ma等峰值则揭示了与Rodinia超大陆解体有关的幕式岩浆活动。
In the geological history of the assembly and breakup of the supercontinent Rodinia on the Earth during the Neoproterozoic,there once occurred two phases of global glacial events in the Sturtian and Marinoan epoches.Previous studies of isotope ages show that the initiation and termination of the Sturtian glacial epoch are dated at 717 Ma and 660 Ma,while the termination of the Marinoan glacial epoch is dated at 635 Ma. However,the initiation of the Marinoan glacial epoch remains uncertain. The tillites from the Nanhuan Gucheng Formation and Nantuo Formation in southern China respectively represent the depositional records of the Sturtian and Marinoan glacial deposits,and the Datangpo Formation is represented by the interglacial deposits. The present paper reports the LA-ICP-MS zircon U-Pb age determinations of the mudstones from the topmost part of the Datangpo Formation in the Bajiaohe section,Zouma area,western Hubei. 62 spots of 62 zircon grains give 60 concordia ages(concordency >90%)ranging between 651 Ma and 2435 Ma,of which 52 zircon U-Pb ages vary from 751 Ma to 851 Ma,with the peak age of about 794 Ma. The youngest zircon U-Pb age is in general agreement with that reported by the predecessors in the adjacent areas,and thus the initiation of the Marinoan glacial epoch may be deduced to be later than 651 Ma. The detrital zircons have the Yangtze affinity,and probably originated from the central Hubei palaeocontinent and northern Yangtze landmass. The peak age of about 850 Ma within the main age range of 751 Ma to 851 Ma may record the collision and amalgamation events occurred in the Yangtze platform and Cathaysia fold zone,while the peak ages of about 820 Ma,800 Ma and 760 Ma may record the episodic magmatism associated with the breakup of the supercontinent Rodinia.
In the geological history of the assembly and breakup of the supercontinent Rodinia on the Earth during the Neoproterozoic,there once occurred two phases of global glacial events in the Sturtian and Marinoan epoches.Previous studies of isotope ages show that the initiation and termination of the Sturtian glacial epoch are dated at 717 Ma and 660 Ma,while the termination of the Marinoan glacial epoch is dated at 635 Ma. However,the initiation of the Marinoan glacial epoch remains uncertain. The tillites from the Nanhuan Gucheng Formation and Nantuo Formation in southern China respectively represent the depositional records of the Sturtian and Marinoan glacial deposits,and the Datangpo Formation is represented by the interglacial deposits. The present paper reports the LA-ICP-MS zircon U-Pb age determinations of the mudstones from the topmost part of the Datangpo Formation in the Bajiaohe section,Zouma area,western Hubei. 62 spots of 62 zircon grains give 60 concordia ages(concordency >90%)ranging between 651 Ma and 2435 Ma,of which 52 zircon U-Pb ages vary from 751 Ma to 851 Ma,with the peak age of about 794 Ma. The youngest zircon U-Pb age is in general agreement with that reported by the predecessors in the adjacent areas,and thus the initiation of the Marinoan glacial epoch may be deduced to be later than 651 Ma. The detrital zircons have the Yangtze affinity,and probably originated from the central Hubei palaeocontinent and northern Yangtze landmass. The peak age of about 850 Ma within the main age range of 751 Ma to 851 Ma may record the collision and amalgamation events occurred in the Yangtze platform and Cathaysia fold zone,while the peak ages of about 820 Ma,800 Ma and 760 Ma may record the episodic magmatism associated with the breakup of the supercontinent Rodinia.
引文
[1]郑永飞.新元古代岩浆活动与全球变化[J].科学通报,2003,(16):1705-1720.
[2]杜秋定,汪正江,王剑,等.湘中长安组碎屑锆石LA-ICP-MS U-Pb年龄及其地质意义[J].地质论评,2013,59(2):334-344.
[3]潘桂棠,陆松年,肖庆辉,等.中国大地构造阶段划分和演化[J].地学前缘,2016,23(6):1-23.
[4]李献华,李武显,何斌.华南陆块的形成与Rodinia超大陆聚合-裂解——观察、解释与检验[J].矿物岩石地球化学通报,2012,31(6):543-559.
[5]Wang J,Li Z X. History of Neoproterozoic rift basins in South China:implications for Rodinia break-up[J]. Precambrian Research,2003,122(1):141-158.
[6]包秀娟.华南新元古代大塘坡组旋回地层学研究及其意义[D].北京:中国地质大学(北京),2016.
[7]Hoffman P F,Kaufman A J,Halverson G P,et al. A Neoproterozoic snowball Earth[J]. Science,1998,281(5381):1342-1346.
[8]Hoffman,P. F,Schrag,D. P. The Snowball Earth hypothesis:Testing the limits of global change[J]. Terra Nova,2002,14(3):129-155.
[9]Lan Z,Li X,Zhu M,et al. A rapid and synchronous initiation of the widespread Cryogenian glaciations[J]. Precambrian Research,2014,255:401-411.
[10]Macdonald F A,Schmitz M D,Crowley J L,et al. Calibrating the Cryogenian[J]. Science,2010,327(5970):1241-1243.
[11]Rooney A D,Strauss J V,Brandon A D,et al. A Cryogenian chronology:Two long-lasting synchronous Neoproterozoic glaciations[J]. Geology,2015,43(5). 459-462.
[12]储雪蕾,Wolfgang,Todt,等.南华—震旦系界线的锆石U-Pb年龄[J].科学通报,2005,50(6):600-602.
[13]蔡娟娟,崔晓庄,兰中伍,等.华南扬子陆块成冰纪冰川作用的启动时限及其全球对比[J].古地理学报,2018,20(1):65-86.
[14]Zhang S,Jiang G,Han Y. The age of the Nantuo Formation and Nantuo glaciation in South China[J]. Terra Nova,2010,20(4):289-294.
[15]Liu P,Li X,Chen S,et al. New SIMS U-Pb zircon age and its constraint on the beginning of the Nantuo glaciations[J].Science Bulletin,2015,60(10):958-963.
[16]罗亮,孙志明,马志鑫,等.黔东渝东南地区南华纪沉积序列与沉积环境演变[J].地质科技情报,2015,34(2)27-35.
[17]Zong K Q,Klemd R.,Yuan Y,et al. The assembly of Rodinia:The correlation of early Neoproterozoic(ca. 900 Ma)high-grade metamorphism and continental arc formation in the southern Beishan Orogen,southern Central Asian Orogenic Belt(CAOB)[J]. Precambrian Research,2017,290(12):32-48.
[18]Hu Z,Zhang W,Liu Y,et al."Wave"signal-smoothing and mercury-removing device for laser ablation quadrupole and multiple collector ICPMS analysis:application to lead isotope analysis.[J]. Analytical Chemistry,2015,87(2):1152-1157.
[19]Liu Y,Gao S,Hu Z,et al. 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[J]. Journal of Petrology,2010,51(51):537-571.
[20]Ludwig K R. User's Manual for Isoplot 3. 00. A geochronological toolkit for Microsoft Excel[M]. Special Publication No. 4a.Berkeley Geochronology Center,Berkeley,CA. 2003.
[21]徐云飞,丛峰,刘军平,等.滇西澜沧岩群碎屑锆石U-Pb定年及其地质意义[J].沉积与特提斯地质,2018,38(2):103-112.
[22]Dickinson W R,Gehrels G E. Use of U-Pb ages of detrital zircons to infer maximum depositional ages of strata:A test against a Colorado Plateau Mesozoic database[J]. Earth&Planetary Science Letters,2009,288(1):115-125
[23]赵彦彦,郑永飞.全球新元古代冰期的记录和时限[J].岩石学报,2011,27(2):545-565.
[24]郭佩,刘池洋,王建强,等.碎屑锆石年代学在沉积物源研究中的应用及存在问题[J].沉积学报,2017,35(1):46-56.
[25]佘振兵.中上扬子上元古界—中生界碎屑锆石年代学研究[D].中国地质大学,2007.
[26]宋芳,牛志军,何篧砚,等.中扬子地区南华纪早期碎屑锆石U-Pb年龄及其对物源特征和古地理格局的约束[J].地质学报,2016,90(10):2661-2680.
[27]胡蓉.三峡地区南沱组与陡山沱组地球化学特征及其意义[D].合肥:中国科学技术大学,2016.
[28]马大铨,杜绍华,肖志发.黄陵花岗岩基的成因[J].岩石矿物学杂志,2002,(2):151-161.
[29]凌文黎,高山,程建萍,等.扬子陆核与陆缘新元古代岩浆事件对比及其构造意义——来自黄陵和汉南侵入杂岩ELA-ICPMS锆石U-Pb同位素年代学的约束[J].岩石学报,2006,22(2):387-396.
[30]凌文黎,高山,张本仁,等.扬子陆核古元古代晚期构造热事件与扬子克拉通演化[J].科学通报,2000(21):2343-2348.
[31]Ye M F,Li X H,Li W X,et al. SHRIMP zircon U-Pb geochronological and whole-rock geochemical evidence for an early Neoproterozoic Sibaoan magmatic arc along the southeastern margin of the Yangtze Block[J]. Gondwana Research,2007,12(1):144-156.
[32]Li W X,Li X H,Li Z X,et al. Obduction-type granites within the NE Jiangxi Ophiolite:Implications for the final amalgamation between the Yangtze and Cathaysia Blocks[J]. Gondwana Research,2008,13(3):288-301.
[2]杜秋定,汪正江,王剑,等.湘中长安组碎屑锆石LA-ICP-MS U-Pb年龄及其地质意义[J].地质论评,2013,59(2):334-344.
[3]潘桂棠,陆松年,肖庆辉,等.中国大地构造阶段划分和演化[J].地学前缘,2016,23(6):1-23.
[4]李献华,李武显,何斌.华南陆块的形成与Rodinia超大陆聚合-裂解——观察、解释与检验[J].矿物岩石地球化学通报,2012,31(6):543-559.
[5]Wang J,Li Z X. History of Neoproterozoic rift basins in South China:implications for Rodinia break-up[J]. Precambrian Research,2003,122(1):141-158.
[6]包秀娟.华南新元古代大塘坡组旋回地层学研究及其意义[D].北京:中国地质大学(北京),2016.
[7]Hoffman P F,Kaufman A J,Halverson G P,et al. A Neoproterozoic snowball Earth[J]. Science,1998,281(5381):1342-1346.
[8]Hoffman,P. F,Schrag,D. P. The Snowball Earth hypothesis:Testing the limits of global change[J]. Terra Nova,2002,14(3):129-155.
[9]Lan Z,Li X,Zhu M,et al. A rapid and synchronous initiation of the widespread Cryogenian glaciations[J]. Precambrian Research,2014,255:401-411.
[10]Macdonald F A,Schmitz M D,Crowley J L,et al. Calibrating the Cryogenian[J]. Science,2010,327(5970):1241-1243.
[11]Rooney A D,Strauss J V,Brandon A D,et al. A Cryogenian chronology:Two long-lasting synchronous Neoproterozoic glaciations[J]. Geology,2015,43(5). 459-462.
[12]储雪蕾,Wolfgang,Todt,等.南华—震旦系界线的锆石U-Pb年龄[J].科学通报,2005,50(6):600-602.
[13]蔡娟娟,崔晓庄,兰中伍,等.华南扬子陆块成冰纪冰川作用的启动时限及其全球对比[J].古地理学报,2018,20(1):65-86.
[14]Zhang S,Jiang G,Han Y. The age of the Nantuo Formation and Nantuo glaciation in South China[J]. Terra Nova,2010,20(4):289-294.
[15]Liu P,Li X,Chen S,et al. New SIMS U-Pb zircon age and its constraint on the beginning of the Nantuo glaciations[J].Science Bulletin,2015,60(10):958-963.
[16]罗亮,孙志明,马志鑫,等.黔东渝东南地区南华纪沉积序列与沉积环境演变[J].地质科技情报,2015,34(2)27-35.
[17]Zong K Q,Klemd R.,Yuan Y,et al. The assembly of Rodinia:The correlation of early Neoproterozoic(ca. 900 Ma)high-grade metamorphism and continental arc formation in the southern Beishan Orogen,southern Central Asian Orogenic Belt(CAOB)[J]. Precambrian Research,2017,290(12):32-48.
[18]Hu Z,Zhang W,Liu Y,et al."Wave"signal-smoothing and mercury-removing device for laser ablation quadrupole and multiple collector ICPMS analysis:application to lead isotope analysis.[J]. Analytical Chemistry,2015,87(2):1152-1157.
[19]Liu Y,Gao S,Hu Z,et al. 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[J]. Journal of Petrology,2010,51(51):537-571.
[20]Ludwig K R. User's Manual for Isoplot 3. 00. A geochronological toolkit for Microsoft Excel[M]. Special Publication No. 4a.Berkeley Geochronology Center,Berkeley,CA. 2003.
[21]徐云飞,丛峰,刘军平,等.滇西澜沧岩群碎屑锆石U-Pb定年及其地质意义[J].沉积与特提斯地质,2018,38(2):103-112.
[22]Dickinson W R,Gehrels G E. Use of U-Pb ages of detrital zircons to infer maximum depositional ages of strata:A test against a Colorado Plateau Mesozoic database[J]. Earth&Planetary Science Letters,2009,288(1):115-125
[23]赵彦彦,郑永飞.全球新元古代冰期的记录和时限[J].岩石学报,2011,27(2):545-565.
[24]郭佩,刘池洋,王建强,等.碎屑锆石年代学在沉积物源研究中的应用及存在问题[J].沉积学报,2017,35(1):46-56.
[25]佘振兵.中上扬子上元古界—中生界碎屑锆石年代学研究[D].中国地质大学,2007.
[26]宋芳,牛志军,何篧砚,等.中扬子地区南华纪早期碎屑锆石U-Pb年龄及其对物源特征和古地理格局的约束[J].地质学报,2016,90(10):2661-2680.
[27]胡蓉.三峡地区南沱组与陡山沱组地球化学特征及其意义[D].合肥:中国科学技术大学,2016.
[28]马大铨,杜绍华,肖志发.黄陵花岗岩基的成因[J].岩石矿物学杂志,2002,(2):151-161.
[29]凌文黎,高山,程建萍,等.扬子陆核与陆缘新元古代岩浆事件对比及其构造意义——来自黄陵和汉南侵入杂岩ELA-ICPMS锆石U-Pb同位素年代学的约束[J].岩石学报,2006,22(2):387-396.
[30]凌文黎,高山,张本仁,等.扬子陆核古元古代晚期构造热事件与扬子克拉通演化[J].科学通报,2000(21):2343-2348.
[31]Ye M F,Li X H,Li W X,et al. SHRIMP zircon U-Pb geochronological and whole-rock geochemical evidence for an early Neoproterozoic Sibaoan magmatic arc along the southeastern margin of the Yangtze Block[J]. Gondwana Research,2007,12(1):144-156.
[32]Li W X,Li X H,Li Z X,et al. Obduction-type granites within the NE Jiangxi Ophiolite:Implications for the final amalgamation between the Yangtze and Cathaysia Blocks[J]. Gondwana Research,2008,13(3):288-301.
© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号 地址：北京市海淀区学院路29号 邮编：100083 电话：办公室：(+86 10)66554848；文献借阅、咨询服务、科技查新：66554700 |