大息场组——黔东北思南奥陶系—志留系之交的一个新地层单元
|
摘要
黔东北思南鹦鹉溪大息场剖面出露奥陶系—志留系界线处的地层序列,该序列与周缘地区相比较,具有其岩相和生物相的特殊性,以此为据建立新地层单元——大息场组。大息场组实测厚度129.7 m,主体岩性由灰色和灰黄色薄层—中层细砂岩和粉砂岩组成,下部暗色粉砂岩中产出3层笔石,指示该组时限为凯迪期晚期到鲁丹期末期。大息场组的碎屑岩层之间不存在暴露海平面之上的标志,表明这里地处局限的凹陷带,此时黔中古陆以北发生的海退未波及至此。
Ordovician-Silurian transition rocks are special in aspects of time-interval, lithological components and biotic structure at the Daxichang section, Yingwuxi Town, Sinan County of northeast Guizhou Province.The Daxichang Formation, a newly erected lithological unit base on the standard section herein is dominantly composed of thin-medium bedded grey and greyish yellow fine sandstones and siltstones with thickness of about 130 m. Three layers of graptolites sparsely yielded from the dark siltstones of the lower part of the formation are identified, which are correlated to the graptolitic biozonations of the WF1-WF2 of late Katian(Upper Ordovician), LM2 and LM4-LM5 of the Rhuddanian(Llandovery of the Lower Silurian) respectively in ascending order. No lacunae has been recognized from the formation; therefore, we conduct that all the terrigenous debris of the formation were deposited in submarine facies, where maintained a limited depression weakly affected by the regressions frequently occurred elsewhere from the northern seaward of the Qianzhong Land. However, palaeogeographic and palaeoecological isolations are both potentially considered as constraining mechanisms in completeness of graptolitic zonations and inhabitation of benthic fauna.
Ordovician-Silurian transition rocks are special in aspects of time-interval, lithological components and biotic structure at the Daxichang section, Yingwuxi Town, Sinan County of northeast Guizhou Province.The Daxichang Formation, a newly erected lithological unit base on the standard section herein is dominantly composed of thin-medium bedded grey and greyish yellow fine sandstones and siltstones with thickness of about 130 m. Three layers of graptolites sparsely yielded from the dark siltstones of the lower part of the formation are identified, which are correlated to the graptolitic biozonations of the WF1-WF2 of late Katian(Upper Ordovician), LM2 and LM4-LM5 of the Rhuddanian(Llandovery of the Lower Silurian) respectively in ascending order. No lacunae has been recognized from the formation; therefore, we conduct that all the terrigenous debris of the formation were deposited in submarine facies, where maintained a limited depression weakly affected by the regressions frequently occurred elsewhere from the northern seaward of the Qianzhong Land. However, palaeogeographic and palaeoecological isolations are both potentially considered as constraining mechanisms in completeness of graptolitic zonations and inhabitation of benthic fauna.
引文
陈建强,何心一.2004.上扬子区早志留世四射珊瑚的复苏与辐射//戎嘉余,方宗杰主编.生物大灭绝与复苏-来自华南古生代和三叠纪的证据.合肥:中国科学技术大学出版社,187-222,1045-1046.
陈旭,樊隽轩,张元动,王红岩,陈清,王文卉,梁峰,郭伟,赵群,聂海宽,文治东,孙宗元.2015.五峰组及龙马溪组黑色页岩在扬子覆盖区内的划分与圈定.地层学杂志,39(4):351-358.
陈旭,戎嘉余,周志毅,张元动,詹仁斌,刘建波,樊隽轩,2001.上扬子区奥陶-志留纪之交的黔中隆起和宜昌上升.科学通报,46(12):1052-1056.
陈旭,樊隽轩,王文卉,王红岩,聂海宽,石学文,文治东,陈冬阳,李文杰,2017.黔渝地区志留系龙马溪组黑色笔石页岩的阶段性渐进展布模式.中国科学:地球科学,47(6):720-732.
葛治洲,戎嘉余,杨学长,刘耕武,倪寓南,董得源,伍鸿基.1979.西南地区的志留系//中国科学院南京地质古生物研究所编.西南地区碳酸盐生物地层.北京:科学出版社,155-220.
戴新春,黄友庄.1998.刍议黔中隆起及其形成过程中的均衡沉陷作用.贵州工业大学学报:自然科学版,27:23-26.
何熙奇,肖加飞,王尚彦,刘爱民,黎超.2005.黔中隆起研究.贵州地质,22:83-89.
何心一.1978.贵州毕节晚奥陶世观音桥层四射珊瑚动物群//中国地质科学院主编.地层古生物论文集,6辑.北京:地质出版社,1-45.
何心一,陈建强.2003.黔北晚奥陶世和早志留世四射珊瑚新资料.古生物学报,42:174-188.
鞠天吟.1999.黔中隆起之窥见.贵州地质,16:180-184.
李越.2004.华南晚奥陶世至早志留世生物礁的演化历程//戎嘉余,方宗杰主编.生物大灭绝与复苏-来自华南古生代和三叠纪的证据.合肥:中国科学技术大学出版社,187-222,1045-1046.
穆恩之,朱兆玲,陈均远,戎嘉余.1979.西南地区的奥陶系//中国科学院南京地质古生物研究所.西南地区碳酸盐生物地层.北京:科学出版社,108-154.
穆恩之,陈旭,李积金,倪寓南,葛梅钰,林尧坤.1981.华中区晚奥陶世古地理图及其说明书.地层学杂志,5(3):167-170.
倪超,邓小杰,李越,2015.黔东北石阡香树园剖面“龙马溪组”灰岩中的生物多样性.微体古生物学报,32(1):105-113.
倪超,李越,邓小杰.2016a.黔东北石阡香树园剖面志留系香树园组生屑滩微相.微体古生物学报,33(1):94-104.
倪超,李越,于深洋,毛颖颜.2016b.黔东北石阡志留纪最早期生物礁的形态学和古生态学.地质科学,51(3):987-989.
戎嘉余.1979.中国的赫南特贝动物群(Hinrnantia fauna)并论奥陶系与志留系的分界.地层学杂志,3(1):1-28.
戎嘉余,陈旭,王怿,詹仁斌,刘建波,黄冰,唐鹏,吴荣昌,王光旭.2011.奥陶-志留纪之交黔中古陆的变迁:证据与启示.中国科学(D辑):地球科学,41(10):1407-1415.
戎嘉余,詹仁斌.2004.牛场组-上扬子区南部志留系兰多维列统的一个新地层单位.地层学杂志,28(4):300-306.
戎嘉余,陈旭,詹仁斌,樊隽轩,王怿,张元动,李越,黄冰,吴荣昌,王光旭.2010.贵州桐梓县境南部奥陶系-志留系界线地层新认识.地层学杂志,34:337-348.
戎嘉余,王怿,詹仁斌,樊隽轩,黄冰,唐鹏,李越,张小乐,吴荣昌,王光旭,魏鑫.2019.中国志留纪综合地层和时间框架,中国科学:地球科学,49(1):93-114..
曾庆銮,赖才根,徐光洪,倪世钊,周天梅,项礼文,汪啸风,李志宏.1987.奥陶系//汪啸风,倪世钊,曾庆銮,徐光洪,周天梅,李志宏,项礼文,赖才根编.长江三峡地区生物地层学(2):早古生代分册.北京:地质出版社,43-142.
沈志达,梅冥相,曾羽.1990.贵州太康运动的地层学效应-兼论“黔中古陆”的形成.贵州地质,7:91-98.
杨向荣,严德天,张利伟,张宝,徐翰文,刘文慧,郧嘉琳.2018.赫南特冰期古海洋环境转变及其成因机制研究现状.沉积学报,36(2):319-332.
于深洋,李越,毛颖颜.2017.海水深度制约黔东北志留系香树园组生物礁滩的分布.微体古生物学报,34(1):67-76.
张琳娜,樊隽轩,陈清.2016.华南上奥陶统观音桥层的空间分布和古地理重建.科学通报,61(18):2053-2063.
张文堂,许汉奎,陈旭,陈均远,袁克兴,林尧坤,王俊庚.1964.贵州北部的奥陶系//中国科学院南京地质古生物研究所主编.黔北地层现场会议-贵州北部的古生代地层,33-78.
周希云.1990.对“黔中隆起”的几点初步认识.贵州工业学院学报,19:78-79.
Chen Xu,Rong Jia-yu,Mitchell Charles E,Harper David A T,Fan Jun-xuan,Zhang Yuan-dong,Zhan Ren-bin,Wang Zhi-zhe&Wang Yi.1999.Stratigraphy of the Hirnantian Substage from Wangjiawan,Yichang,W.Hubei and Honghuayuan,Tongzi,N.Guizhou,China.Acta Universitatis Carolinae:Geologica,43(1-2):233-236.
Chen Xu,Rong Jia-yu,Mitchell Charles E,Harper David A T,Fan Jun-xuan,Zhan Ren-bin,Zhang Yuan-dong,Li Rong-yu&Wang Yi.2000.Late Ordovician to earliest Silurian graptolite and brachiopod biozonation from the Yangtze region,South China,with a global correlation.Geological Magazine,137:623-650.
Chen Xu,Rong Jia-yu,Li Yue&Boucot A J.2004.Facies patterns and geography of Yangtze region,South China through the Ordovician and Silurian transition.Paleogeography,Paleoclimatology,Paleoecology,204(3-4):353-372.
Fan Jun-xuan,Melchin M J,Chen Xu,Wang Yi,Zhang Yuan-dong,Chen Qing,Chi Zhao-li&Chen Feng.2011.Biostratigraphy and geography of the Ordovician-Silurian Lungmachi black shales in South China.Science China:Earth Science,54:1854-1863.
Fan Jun-xuan,Chen Qing,Melchin M J,Sheets H D,Chen Zhong-yang,Zhang Linna&Hou Xu-dong.2013.Quantitative stratigraphy of the Wufeng and Lungmachi black shales and graptolite evolution during and after the Late Ordovician mass extinction.Palaeogeography,Palaeoclimatology,Palaeoecology,389:96-114.
Feng Xue-qian,Chen Zhong-qiang,Bottjer David J,Wu Si-qi,Zhao Lai-shi,Xu Ya-ling,Shi G R,Huang Yuan-geng,Fang Yu-heng&Tu Chen-yi.2018.Unusual shallow marine matground-adapted benthic biofacies from the Lower Triassic of the northern Paleotethys:Implications for biotic recovery following the end-Permian mass extinction.Earth-Science Reviews,doi.org/10.1016/j.earscirev.2018.07.012.
Kershaw S,Crasquin S,Li Yue,Collin P Y,Forel M B,Mu Xi-nan,Baud A,Wang Y,Xie Shu-cheng,Maurer F&Guo Li.2012.Microbialites and global environmental change across the Permian-Triassic boundary:A synthesis.Geobiology,10:25-47.
Li Yue,Matsumoto Ryo&Kershaw S.2005.Sedimentary and biotic evidence of a warm-water enclave in the cooler oceans of the Latest Ordovician glacial phase,Yangtze Platform,South China.Island Arc,14(4):623-635.
Li Yue&Kershaw S.2003.Reef reconstruction after extinction event of Latest Ordovician in Yangtze Platform,South China.Facies,48:269-284.
Luo Mao,Chen Zhong-qiang,Shi G R,Feng Xue-qian,Yang Hao,Fang Yu-heng&Li Yang.2019.Microbially induced sedimentary structures(MISSs)from the Lower Triassic Kockatea Formation,northern Perth Basin,Western Australia:Palaeoenvironmental implications.Palaeogeography,Palaeoclimatology,Palaeoecology,519:236-247.
Rong Jia-yu&Li Rong-yu.1999.A silicified Hinantian Fauna(latest Ordovician brachiopoda)from Guizhou,southwest China.Journal of Paleontology,73(5):831-849.
Rong Jia-yu,Chen Xu,Su Yang-zheng,Ni Yu-nan,Zhan Ren-bin&Chen Ting-en.2003.Silurian paleogeography of China//Landing E,Johnson ME(eds.),Silurian Lands and Seas-Paleogeography Outside of Laurentia.New York State Museum Bulletin,493:243-298.
Schieber J.1999.Microbial mats in terrigenous clastics:The challenge of identification in the rock record.Palaios,14:3-12.
Schubert J&Bottjer D J.1992.Early Triassic stromatolites as post-mass extinction disaster forms.Geology,20:883-886.
Seilacher A.1964.Sedimen tological classification and nomenclature of trace fossils.Sedimentology,3:253-256.
Seilacher A.1967.Bathymetry of trace fossils.Marine Geology,5:413-428.
Sheehan P M&Harris M T.2000.Early Silurian stromatolites and thrombolites:successful disaster forms after the Late Ordovician mass extinction.Progress of Geological Society of American,Nature Meeting,32:367-368.
Sheehan P M&Harris M T.2004.Microbialite resurgence after the Late Ordovician extinction.Nature,430:75-78.
Wang Guang-xu,Zhan Ren-bin,Deng Zhan-qiu&Yu Chang-min.2014.Latest Ordovician and earliest Silurian tabulate corals of South China.GFF,136(1):90-293.
Wang Guang-xu,Zhan Ren-bin,Percival I G,Huang Bing,Li Yue&Wu Rong-chang.2015.Late Hirnantian(latest Ordovician)carbonate rocks and shelly fossils in Shiqian,northeastern Guizhou,Southwest China.Newsletters on Stratigraphy,48(3):241-252.
Wignall P B&Twitchett R J.1999.Unusual intraclastic limestones in Lower Triassic carbonates and their bearing on the aftermath of the end-Permian mass extinction.Sedimentology,46:303-316.
Yu Shen-yang,Chen Qing,Kershaw Stephen,Li Yue&Li Chao.2018.Upper Ordovician continuous lithological succession in outer-shelf facies,Yangtze Platform,South China:Facies changes and oceanographic reconstruction up to the Late Ordovician Hirnantian glaciation.Island Arc,DOI:10.1111/iar.12259.
陈旭,樊隽轩,张元动,王红岩,陈清,王文卉,梁峰,郭伟,赵群,聂海宽,文治东,孙宗元.2015.五峰组及龙马溪组黑色页岩在扬子覆盖区内的划分与圈定.地层学杂志,39(4):351-358.
陈旭,戎嘉余,周志毅,张元动,詹仁斌,刘建波,樊隽轩,2001.上扬子区奥陶-志留纪之交的黔中隆起和宜昌上升.科学通报,46(12):1052-1056.
陈旭,樊隽轩,王文卉,王红岩,聂海宽,石学文,文治东,陈冬阳,李文杰,2017.黔渝地区志留系龙马溪组黑色笔石页岩的阶段性渐进展布模式.中国科学:地球科学,47(6):720-732.
葛治洲,戎嘉余,杨学长,刘耕武,倪寓南,董得源,伍鸿基.1979.西南地区的志留系//中国科学院南京地质古生物研究所编.西南地区碳酸盐生物地层.北京:科学出版社,155-220.
戴新春,黄友庄.1998.刍议黔中隆起及其形成过程中的均衡沉陷作用.贵州工业大学学报:自然科学版,27:23-26.
何熙奇,肖加飞,王尚彦,刘爱民,黎超.2005.黔中隆起研究.贵州地质,22:83-89.
何心一.1978.贵州毕节晚奥陶世观音桥层四射珊瑚动物群//中国地质科学院主编.地层古生物论文集,6辑.北京:地质出版社,1-45.
何心一,陈建强.2003.黔北晚奥陶世和早志留世四射珊瑚新资料.古生物学报,42:174-188.
鞠天吟.1999.黔中隆起之窥见.贵州地质,16:180-184.
李越.2004.华南晚奥陶世至早志留世生物礁的演化历程//戎嘉余,方宗杰主编.生物大灭绝与复苏-来自华南古生代和三叠纪的证据.合肥:中国科学技术大学出版社,187-222,1045-1046.
穆恩之,朱兆玲,陈均远,戎嘉余.1979.西南地区的奥陶系//中国科学院南京地质古生物研究所.西南地区碳酸盐生物地层.北京:科学出版社,108-154.
穆恩之,陈旭,李积金,倪寓南,葛梅钰,林尧坤.1981.华中区晚奥陶世古地理图及其说明书.地层学杂志,5(3):167-170.
倪超,邓小杰,李越,2015.黔东北石阡香树园剖面“龙马溪组”灰岩中的生物多样性.微体古生物学报,32(1):105-113.
倪超,李越,邓小杰.2016a.黔东北石阡香树园剖面志留系香树园组生屑滩微相.微体古生物学报,33(1):94-104.
倪超,李越,于深洋,毛颖颜.2016b.黔东北石阡志留纪最早期生物礁的形态学和古生态学.地质科学,51(3):987-989.
戎嘉余.1979.中国的赫南特贝动物群(Hinrnantia fauna)并论奥陶系与志留系的分界.地层学杂志,3(1):1-28.
戎嘉余,陈旭,王怿,詹仁斌,刘建波,黄冰,唐鹏,吴荣昌,王光旭.2011.奥陶-志留纪之交黔中古陆的变迁:证据与启示.中国科学(D辑):地球科学,41(10):1407-1415.
戎嘉余,詹仁斌.2004.牛场组-上扬子区南部志留系兰多维列统的一个新地层单位.地层学杂志,28(4):300-306.
戎嘉余,陈旭,詹仁斌,樊隽轩,王怿,张元动,李越,黄冰,吴荣昌,王光旭.2010.贵州桐梓县境南部奥陶系-志留系界线地层新认识.地层学杂志,34:337-348.
戎嘉余,王怿,詹仁斌,樊隽轩,黄冰,唐鹏,李越,张小乐,吴荣昌,王光旭,魏鑫.2019.中国志留纪综合地层和时间框架,中国科学:地球科学,49(1):93-114..
曾庆銮,赖才根,徐光洪,倪世钊,周天梅,项礼文,汪啸风,李志宏.1987.奥陶系//汪啸风,倪世钊,曾庆銮,徐光洪,周天梅,李志宏,项礼文,赖才根编.长江三峡地区生物地层学(2):早古生代分册.北京:地质出版社,43-142.
沈志达,梅冥相,曾羽.1990.贵州太康运动的地层学效应-兼论“黔中古陆”的形成.贵州地质,7:91-98.
杨向荣,严德天,张利伟,张宝,徐翰文,刘文慧,郧嘉琳.2018.赫南特冰期古海洋环境转变及其成因机制研究现状.沉积学报,36(2):319-332.
于深洋,李越,毛颖颜.2017.海水深度制约黔东北志留系香树园组生物礁滩的分布.微体古生物学报,34(1):67-76.
张琳娜,樊隽轩,陈清.2016.华南上奥陶统观音桥层的空间分布和古地理重建.科学通报,61(18):2053-2063.
张文堂,许汉奎,陈旭,陈均远,袁克兴,林尧坤,王俊庚.1964.贵州北部的奥陶系//中国科学院南京地质古生物研究所主编.黔北地层现场会议-贵州北部的古生代地层,33-78.
周希云.1990.对“黔中隆起”的几点初步认识.贵州工业学院学报,19:78-79.
Chen Xu,Rong Jia-yu,Mitchell Charles E,Harper David A T,Fan Jun-xuan,Zhang Yuan-dong,Zhan Ren-bin,Wang Zhi-zhe&Wang Yi.1999.Stratigraphy of the Hirnantian Substage from Wangjiawan,Yichang,W.Hubei and Honghuayuan,Tongzi,N.Guizhou,China.Acta Universitatis Carolinae:Geologica,43(1-2):233-236.
Chen Xu,Rong Jia-yu,Mitchell Charles E,Harper David A T,Fan Jun-xuan,Zhan Ren-bin,Zhang Yuan-dong,Li Rong-yu&Wang Yi.2000.Late Ordovician to earliest Silurian graptolite and brachiopod biozonation from the Yangtze region,South China,with a global correlation.Geological Magazine,137:623-650.
Chen Xu,Rong Jia-yu,Li Yue&Boucot A J.2004.Facies patterns and geography of Yangtze region,South China through the Ordovician and Silurian transition.Paleogeography,Paleoclimatology,Paleoecology,204(3-4):353-372.
Fan Jun-xuan,Melchin M J,Chen Xu,Wang Yi,Zhang Yuan-dong,Chen Qing,Chi Zhao-li&Chen Feng.2011.Biostratigraphy and geography of the Ordovician-Silurian Lungmachi black shales in South China.Science China:Earth Science,54:1854-1863.
Fan Jun-xuan,Chen Qing,Melchin M J,Sheets H D,Chen Zhong-yang,Zhang Linna&Hou Xu-dong.2013.Quantitative stratigraphy of the Wufeng and Lungmachi black shales and graptolite evolution during and after the Late Ordovician mass extinction.Palaeogeography,Palaeoclimatology,Palaeoecology,389:96-114.
Feng Xue-qian,Chen Zhong-qiang,Bottjer David J,Wu Si-qi,Zhao Lai-shi,Xu Ya-ling,Shi G R,Huang Yuan-geng,Fang Yu-heng&Tu Chen-yi.2018.Unusual shallow marine matground-adapted benthic biofacies from the Lower Triassic of the northern Paleotethys:Implications for biotic recovery following the end-Permian mass extinction.Earth-Science Reviews,doi.org/10.1016/j.earscirev.2018.07.012.
Kershaw S,Crasquin S,Li Yue,Collin P Y,Forel M B,Mu Xi-nan,Baud A,Wang Y,Xie Shu-cheng,Maurer F&Guo Li.2012.Microbialites and global environmental change across the Permian-Triassic boundary:A synthesis.Geobiology,10:25-47.
Li Yue,Matsumoto Ryo&Kershaw S.2005.Sedimentary and biotic evidence of a warm-water enclave in the cooler oceans of the Latest Ordovician glacial phase,Yangtze Platform,South China.Island Arc,14(4):623-635.
Li Yue&Kershaw S.2003.Reef reconstruction after extinction event of Latest Ordovician in Yangtze Platform,South China.Facies,48:269-284.
Luo Mao,Chen Zhong-qiang,Shi G R,Feng Xue-qian,Yang Hao,Fang Yu-heng&Li Yang.2019.Microbially induced sedimentary structures(MISSs)from the Lower Triassic Kockatea Formation,northern Perth Basin,Western Australia:Palaeoenvironmental implications.Palaeogeography,Palaeoclimatology,Palaeoecology,519:236-247.
Rong Jia-yu&Li Rong-yu.1999.A silicified Hinantian Fauna(latest Ordovician brachiopoda)from Guizhou,southwest China.Journal of Paleontology,73(5):831-849.
Rong Jia-yu,Chen Xu,Su Yang-zheng,Ni Yu-nan,Zhan Ren-bin&Chen Ting-en.2003.Silurian paleogeography of China//Landing E,Johnson ME(eds.),Silurian Lands and Seas-Paleogeography Outside of Laurentia.New York State Museum Bulletin,493:243-298.
Schieber J.1999.Microbial mats in terrigenous clastics:The challenge of identification in the rock record.Palaios,14:3-12.
Schubert J&Bottjer D J.1992.Early Triassic stromatolites as post-mass extinction disaster forms.Geology,20:883-886.
Seilacher A.1964.Sedimen tological classification and nomenclature of trace fossils.Sedimentology,3:253-256.
Seilacher A.1967.Bathymetry of trace fossils.Marine Geology,5:413-428.
Sheehan P M&Harris M T.2000.Early Silurian stromatolites and thrombolites:successful disaster forms after the Late Ordovician mass extinction.Progress of Geological Society of American,Nature Meeting,32:367-368.
Sheehan P M&Harris M T.2004.Microbialite resurgence after the Late Ordovician extinction.Nature,430:75-78.
Wang Guang-xu,Zhan Ren-bin,Deng Zhan-qiu&Yu Chang-min.2014.Latest Ordovician and earliest Silurian tabulate corals of South China.GFF,136(1):90-293.
Wang Guang-xu,Zhan Ren-bin,Percival I G,Huang Bing,Li Yue&Wu Rong-chang.2015.Late Hirnantian(latest Ordovician)carbonate rocks and shelly fossils in Shiqian,northeastern Guizhou,Southwest China.Newsletters on Stratigraphy,48(3):241-252.
Wignall P B&Twitchett R J.1999.Unusual intraclastic limestones in Lower Triassic carbonates and their bearing on the aftermath of the end-Permian mass extinction.Sedimentology,46:303-316.
Yu Shen-yang,Chen Qing,Kershaw Stephen,Li Yue&Li Chao.2018.Upper Ordovician continuous lithological succession in outer-shelf facies,Yangtze Platform,South China:Facies changes and oceanographic reconstruction up to the Late Ordovician Hirnantian glaciation.Island Arc,DOI:10.1111/iar.12259.
© 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 |