汪啸风,Svend Stouge,王传尚,J?rg Maletz,闫春波,Gabriella Bagnoli

• 1:中国地质调查局武汉中心
• 2:哥本哈根大学自然历史博物馆
• 3:柏林自由大学地质研究所
• 4:比萨大学地球科学系

摘要(Abstract)：

基于吉林白山大阳岔小阳桥剖面高精度多学科交叉研究,综合高分辨率生物、层序、化学和磁性地层学的再研究成果,国际奥陶系分会于2019年5月表决通过了中国北方小阳桥剖面为奥陶系底界的全球辅助层型剖面和点(ASSP),即新修的标准辅助界线层型(SABS)(Martinetal.,2022a,2022b),从而为国内外其他区块寒武系-奥陶系界线的精确划分和对比提供了新依据。据此,本文讨论了以下剖面的寒武系-奥陶系界线精确划分与对比问题:位于华夏地块大陆边缘岛弧或弧后盆地相的广东台山新厂阶命名剖面,分别位于扬子地块台地、陆棚-斜坡和斜坡-盆地相的湖北宜昌黄花场两河口剖面、江西修水武宁剖面和湖南常德瓦尔岗剖面,分别位于中朝地块台地和台缘的河北唐山赵阁庄剖面和山东青州饶王山剖面,位于新疆塔里木地块巴楚—西边大板塔格一带寒武系-奥陶系界线所在剖面,位于加拿大纽芬兰绿岬GSSP剖面,以及位于美国犹他州劳森湾的ASSP剖面。值得注意的是,新建立的小阳桥ASSP剖面位于陆棚-斜坡过渡地带,在古地理位置上正好处于浅水碳酸盐台地(如美国劳森湾ASSP)与深水下斜坡(如加拿大绿岬GSSP)和深水下斜坡-盆地(如中国湖南瓦尔岗(Wargang或Wa’ergan)剖面之间的关键位置,从而成为连接他们之间的纽带和对比标志,并据此提高国内外相关界线划分与对比的准确性。此外,小阳桥ASSP详细的生物、沉积、化学和磁性地层分析揭示了绿岬GSSP剖面所指定的GSSP生物和地球化学标志,说明绿岬GSSP剖面的寒武系-奥陶系界线应对比于小阳桥ASSP剖面的标志性块状叠层石石灰岩(0m)之上的第24层(BD24)底部(19.9±0.2m);生物地层学上,该界线位于牙形石Cordylodusintermedius带上部(Cordyloduslindstromi带底界之下1.5m),在最早的浮游笔石(Rhabdinoporaproparabola)首现(FAD)层位(BD26)之下1 m处。层序地层、海平面变化、事件地层和化学地层研究表明,奥陶系底界位于全球弓头虫(Acerocare)低水位事件之下、稀土元素地球化学异常(REE)之上,继之出现最大碳同位素(δ13Ccarb)正偏移(no.3)。这些物理和化学变化为破解全球寒武系-奥陶系界线的精确划分与对比问题,特别是为解决不同大陆和相区间的寒武系-奥陶系界线的精确划分和对比问题,增添了额外的依据。

关键词(KeyWords)： 小阳桥剖面;全球辅助界线层型剖面和点;寒武系-奥陶系界线;高分辨率地层学;牙形石;笔石

Abstract:

Keywords:

基金项目(Foundation): 国科学技术部和中国地质调查局基础研究项目(2015FY310100-7、DD20160120-04)共同资助

作者(Author): 汪啸风,Svend Stouge,王传尚,J?rg Maletz,闫春波,Gabriella Bagnoli

DOI: 10.19839/j.cnki.dcxzz.2023.0007

参考文献(References)：

• 金玉琴,汪啸风.1977.湘中白水溪组笔石群的发现和桥亭子组的多枝笔石[M].北京:地质出版社.
• 穆恩之.1974.正笔石及正笔石式树形笔石的演化、分类和分布[J].中国科学,2:175-183.
• 彭善池.2018.寒武纪[M]//全国地层委员会(编).中国地层表(2014)说明书.北京:地质出版社,71-99.
• 汪啸风.2016.中国南方构造古地理及年代与生物地层划分与对比[J].地学前缘,23:253-267.
• 汪啸风,刘义仁,周国强.1979.广东台山早奥陶世新厂组笔石[J].古生物学报,18(5):493-504.
• 王成源,王志浩.2016.中国牙形刺生物地层[M].杭州:浙江大学出版社.
• 王志浩,甄勇毅,张元动,吴荣昌.2016.中国华北不同相区奥陶纪牙形刺生物地层的再认识[J].地层学杂志,46(1):1-16.
• 武桂春,姚建新,纪占胜,刘书才.2005.山东青州地区寒武系-奥陶系界线研究的新进展[J].古生物学报,44(4):106-116.
• 俞剑华,刘怀宝,方一亭.1984.江西修水流域新厂期(早奥陶世)反称笔石科[J].古生物学报,23(5):532-542.
• 曾庆銮,倪世钊,徐光洪,周天梅,汪啸风,李志宏,项礼文,赖才根.1987.奥陶系[M]//汪啸风等.长江三峡生物地层学,早古生代分册.北京:地质出版社,43-197.
• 张师本.2003.塔里木盆地周缘地层考察指南[M].北京:石油工业出版社.
• 张师本,高琴琴.1992.塔里木盆地震旦纪至二叠纪地层古生物(II).柯坪-巴楚分册[M].北京:石油工业出版社.
• 张元动,詹仁斌,王志浩,袁文伟,方翔,梁艳,燕夔,王玉净,梁昆,张俊鹏,陈挺恩,周志强,陈清,全胄完,马譞,李文杰,武学进,魏鑫.2020.中国奥陶纪地层及标志性化石图集[M].杭州:浙江大学出版社.
• 张元动,詹仁斌,甄勇毅,王志浩,袁文伟,方翔,马譞,张俊鹏.2019.中国奥陶纪综合地层和时间框架[J].中国科学:地球科学,49:66-92.
• 周志毅.2001.塔里木盆地各纪地层[M].北京:科学出版社.
• 周志毅,陈旭,王志浩,王宗哲,李军,耿良玉,方宗杰,乔新东,张太荣.1990.奥陶系[M]//周志毅,陈丕基.塔里木生物地层和地质演化.北京:科学出版社,56-130.
• Adrain J M,Westrop S R.2006.New earliest Ordovician trilobite genus Millardicurus:the oldest known hystricurid[J].Journal of Paleontology,80:650-671.
• Albanesi G L M,Giuliano E,Pacheco F E,Ortega G,Monaldi R.2015.Conodonts from Cambrian Ordovician Boundary in the Cordillera Oriental,NW Argentina[J].Stratigraphy,12(3-4):237-256.
• Bagnoli G,Barnes C R,Stevens R K.1987.Lower Ordovician (Tremadocian) conodonts from Broom Point and Green Point,Western Newfoundland[J].Bollettino della SocietàPaleontologica Italiana,25:145-158.
• Barnes C R.1988.The proposed Cambrian-Ordovician Global Boundary Stratotype and Point (GSSP) in Western Newfoundland,Canada[J].Geological Magazine,125:381-414.
• Bergstr?m S M,Chen X.Gutiérrez-marco J C,Dronov A.2009a.The new chronostratigraphic classification of the Ordovician System and its relations to major regional series and stages and to δ13C chemostratigraphy[J].Lethaia,42:97-107.
• Bergstr?m S M,Chen X,Schmitz B,Young S,Rong J Y,Saltzman M R.2009b.First documentation of the Ordovician Guttenberg δ13C excursion(GICE) in Asia:Chemostratigraphy of the Pagoda and Yanwashan formations in southeastern China[J].Geological Magazine,146:1-11.
• Bulman O M B.1954.The graptolite fauna of the Dictyonema shales of the Oslo region[J].Norsk Geologisk Tidsskrift,33(1-2):1-40.
• Bulman O M B.1970.A new Dictyonema fauna from the Salmien of the Stavelot Massif (with a preface by F.Geukens)[J].Bulletin de la Societébelge Geologie,Paleontologie,Hydrologie,79:213-224.
• Chen J Y.1986.Aspects of Cambrian-Ordovician boundary in Dayancha,China.Contribution to Dayangcha International Conference on CambrianOrdovician Boundary[M].Beijing:China Prospect Publishing House.
• Chen J Y,Qian Y Y,Lin Y K,Zhang J M,Wang Z H,Yin L M,Erdtmann BD.1985.Study on Cambrian-Ordovician boundary strata and its biota in Dayangcha,Hunjiang,Jilin,China[M].Beijing:China Prospect Publishing House.
• Chen J Y,Qian Y Y,Zhang J M,Lin Y K,Yin L M,Wang Z H,Wang Z Z,Yang J D,Wang Y X.1988.The recommended Cambrian-Ordovician boundary stratotype of the Xiaoyangqiao Section (Dayangcha,Jilin Province),China[J].Geological Magazine,125:415-444.
• Chen J Y,Zhang J M,Nicoll R S,Nowlan G S.1995a.Carbon and oxygen isotopes in the carbonate rocks within the Cambrian-Ordovicina boundary interval at Dayangcha,China[J].Acta Palaeontologica Sinica,34(4):393-427.
• Chen X,Rong J Y,Fan J X,Zhan R B,Mitchell C E,Harper D A T,Melchin M J,Peng P A,Finney S C,Wang X F.2006.The global boundary stratotype section and point (GSSP) for the base of the Hirnantian Stage (the uppermost of the Ordovician System)[J].Episodes,29:183-196.
• Chen X,Rong J Y,Wang X F,Wang Z H,Zhang Y D,Zhan R B.1995b.Correlation of the Ordovician rocks of China[J].International Union of Geological Sciences Publication,30(1):1-104.
• Cooper R A,Maletz J,Wang H F,Erdtmann B D.1998.Taxonomy and evolution of earliest Ordovician graptoloids[J].Norsk Geologisk Tidsskrift,78(1):3-32.
• Cooper R A,Nowlan G S.1999.Proposed Global Stratotype Section and Point for the base of the Ordovician System[J].Ordovician News,16:21.
• Cooper R A,Nowlan G S,Williams S H.2001.Global Stratotype Section and Point for base of the Ordovician System[J].Episodes,24(1):19-28.
• Cowie J.1986.Guidelines for boundary straatypes[J].Episodes,9(2):78-82.
• Dong X P,Zhang H Q.2017.Middle Cambrian through lowermost Ordovician conodonts from Hunan,South China[J].Journal of Paleontology,91:1-89.
• Dubinina S V.2000.Konodonty i zonal’naya stratigrafiya pogranichnykh otlozhenii kembriya i ordovika[Conodonts and zonal stratigraphy of the boundary interval of the Cambrian and Ordovician][M].Saint Petersburg:Transactions of the Russian Academy of Sciences,Geological Institute.(in Russian)
• Erdtmann B D.1982.A reorganization and proposed phylogenetic classifi Dronov A cation of planktic Tremadoc (early Ordovician) dendroid graptolites[J].Norsk Geologisk Tidsskrift,62(2):121-145.
• Erdtmann B D.1986.Review of lithofacies and graptolite-based biofacies of three critical Cambrian-Ordovician boundary stratotype sections[M]//Chen J (ed.).Aspects of Cambrian-Ordovician boundary in Dayangcha,China.Beijing:China Prospect Publishing House.
• Erdtmann B D.1988.The earliest Ordovician nematophorid graptolites:taxonomy and correlation[J].Geological Magazine,125:327-348.
• Fan J X,Peng P A,Melchin M J.2009.Carbon isotopes and event stratigraphy near the Ordovician-Silurian boundary,Yichang,South China[J].Palaeogeogr Palaeoclimatol Palaeoecol,276:160-169.
• Fortey R A,Harper A T,Ingham J K,Owen A W,Rushton A W A.1995.Areview of the Ordovician series and states from the historical type area[J].Geological Magazine,1-32:15-30.
• Fortey R A,Landing E,Skevington D.1982.Cambrian-Ordovician boundary sections in the Cow Head Group,western Newfoundland[A]//Bassett M G,Dean W T (eds.).The Cambrian-Ordovician boundary:sections,fossil distributions,and correlations.National Museum of Wales,Geological Series,3:227.
• Frakes L A,Francis J E,Syktus J I.2005.Climate Modes of the Phanerozoic[M].Cambridge:Cambridge University Press.
• Guo H J,Duan J Y,An S L.1982.Cambrian-Ordovician boundary in the North China Platform with description of trilobites[J].Bulletin of Changchun College,3:9-28.
• Haq B U,Schutter S R.2008.A chronology of Paleozoic sea-level changes[J].Science,322(5898):64-68.
• Harris W J,Keble R A.1928.The Staurograptus bed of Victoria[J].Proceedings of the Royal Society of Victoria,40(N.S.)(2):91-95.
• Hearing T W,Harvey T H P,Williams M,Leng M J,Lamb A L,Wilby P R,Gabbott S E,Pohl A,Donnadieu Y.2018.An early Cambrian greenhouse climate[J].Science Advances,4:1-11.
• Hedberg H D.1976.International stratigraphic guide:a guide to stratigraphic classification terminology and procedure[M].New York:John Wiley&Sons.
• Hintze L F.1951.Lower Ordovician detailed stratigraphic sections forwestern Utah[J].Utah Geological and Mineralogical Survey Bulletin,39:99.
• Hintze L F.1953.Lower Ordovician trilobites from western Utah[J].Utah Geological and Mineralogical Survey,Bulletin,48:249.
• Lin Y K.1986.A new planktonic graptolite fauna[M]//Chen J (ed.).Aspects of Cambrian-Ordovician boundary in Dayangcha,China.Hefei:China Prospect Publishing House,224-254.
• Lu Y H.1984.Report on the Cambrian-Ordovician boundary work in Episodes Vol.44,No.4381,China[M]//Nanjing Institute of Geology and Palaeontology,Academia Sinica (ed.).Stratigraphy and palaeontology of systemic boundaries in China,Cambrian and Ordovician boundary(1).Hefei:Anhui Science and Technology Publishing House,1-8.
• Lu Y H,Lin H L.1984.Late Cambrian and earliest Ordovician trilobites of Jiangshan-Changshan area,Zhejiang[M]//Nanjing Instituteof Geology and Palaeontology,Academia Sinica (ed.).Stratigraphy and palaeontology of systematic boundaries in China,Cambrian and Ordovician boundary(1).Hefei:Anhui Science and Technology Publishing House,45-143.
• Martin J H,Marie-Pierre A,Werner E P,Mike Walker.2022a.The Standard Auxiliary Boundary Stratotype:a proposed replacement for the Auxiliary Stratotype Point in supporting a Global boundary Stratotype Section and Point (GSSP)[J].Episodes,https://doi.org/10.18814/epiiugs/2022/022012
• Martin J H,Marie-Pierre A,Werner E P,Mike Walker.2022b.Standard Auxiliary Boundary Stratotype (SABS) approved to support the Global boundary Stratotype Section and Point (GSSP)[J].Episodes,46(1):99-100.
• Maletz J,Wang X F,Wang C S.2022.Early Tremadocian (Ordovician)graptolite biostratigraphy and correlation[J].Palaeoworld,https://doi.org/10.1016/j.palwor.2022.03.010
• Miller J F.1980.Taxonomic revisions of some Upper Cambrian and Lower Ordovician conodonts with comments on their evolution[J].University of Kansas,Paleontological Contributions,99:1-39.
• Miller J F.1988.Conodonts as biostratigraphic tools for redefinition and correlation of the Cambrian-Ordovician Boundary[J].Geological Magazine,125:349-362.
• Miller J F.1992.The Lange Ranch Eustatic Event:a regressive-transgressive couplet near the base of the Ordovician System[M]//Webby B D,Laurie J R (eds).Global Perspectives on Ordovician Geology.Rotterdam:A.A.Balkema,396-407.
• Miller J F.2016.The Auxiliary Boundary Stratigraphic Section and Point(ASSP) for the base of the Ordovician System at Lawson Cove,Ibex Area,Utah,USA[M]//McIlroy D (ed.).International Symposium on the Ediacaran-Cambrian Transition,Abstract Volume:76.
• Miller J F.2019.Study and use of Upper Cambrian to Lower Ordovician conodonts in central,southern,and western Laurentia,1933-2018[J].Palaeobiodiversity and Palaeoenvironments,https://doi.org/10.1007/s12549-019-00380-9
• Miller J F,Evans K R,Dattilo B F.2012.The Great American Carbonate Bank in the miogeocline of western central Utah:tectonic influences on sedimentation[J].American Association of Petroleum Geologists Memoir,98:769-854.
• Miller J F,Evans K R,Ethington R L,Freeman R L,Loch J D,Repetski JE,Ripperdan R L,Taylor J F.2015.Proposed auxiliary Boundary Stratigraphic Section and Point (ASSP) for the base of the Ordovician System at Lawson Cove,Utah,USA[J].Stratigraphy,12(3-4):219-236.
• Miller J F,Evans K R,Loch J D,Ethington R L,Stitt J H,Holmer L,Popov L E.2003.Stratigraphy of the Sauk III Interval (Cambrian-Ordovivian)in the Ibex area,Western Millard County,Utah and Central Texas[J].Brigham Young University Geology Studies,47:21-118.
• Miller J F,Flokstra B R.1999.Graphic correlation of important CambrianOrdovician boundary sections.Quo Vadis Ordovician-Short Papers of the Eigth International Symposium on the Ordovician System[J].Acta Universitatis Carolinae,Geologica,43:81-84.
• Miller J F,Repetski J E,Nicoll R S,Nowlan G,Ethington R L.2014.The conodont Iapetognathus and its value for defining the base of the Ordovician System[J].GFF,136:185-188.
• Nicoll R S,Miller J F,Nowlan G S,Repetski J E,Ethington R L.1999.Iapetonudus (n.gen.) and Iapetognathus Landing,unusual earliest Ordovician multielement conodont taxa and their utility for biostratigraphy[J].Brigham Young University Geology Studies,44:27-101.
• Nowlan G S,Nicoll R S.1995.Re-examination of the conodont biostratigraphy at the Cambrian-Ordovician Xiaoyangqiao Section,Dayangcha,Jilin Province,China[C]//Cooper J D,Droser M L,Finney S C (eds.).Ordovician Odyssey:Short Papers for the Seventh International Symposium on the Ordovician System.Pacific Section of Society for Sedimentary Geology (SEPM),113-116.
• Peng S C.1984.Cambrian-Ordovician boundary in the Cili-Taoyuan border area,northwestern Hunan with description of relative trilobites[M]//Nanjing Institute of Geology and Palaeontology,Academia Sinica(ed.).Stratigraphy and palaeontology of systemic boundaries in China,Cambrian and Ordovician boundary (1).Hefei:Anhui Science and Technology Publishing House,285-405.
• Peng S C.2009.The newly-developed Cambrian biostratigraphic succession and chronostratigraphic scheme for South China[J].Chinese Science Bulletin,54:4161-4170.
• Peng S C,Babcock L E,Cooper R A.2012.The Cambrian Period[M]//Gradstein F M,Ogg G,Schmitz M,Ogg G J (eds.).The Geologic Time Scale 2012.Boston:Elsevier,451-502.
• Popov L E,Holmer L E,Miller J F.2002.Lingulate brachiopods from the Cambrian-Ordovician boundary beds of Utah[J].Journal of Paleontology,76:211-228.
• Pouille L,Danelian T,Maletz J.2014.Radiolarian diversity changes during the Late Cambrian-Early Ordovician transition as recorded in the Cow Head Group of Newfoundland (Canada)[J].Marine Micropaleontology,110:25-41.
• Remane J,Bassett M G,Cowie J W,Gohrbandt K H,Lane H R,Michelsen O,Naiwen W.1996.Revised guidelines for the establishment of Global chronostratigraphic standards by the International Commission on Stratigraphy (ICS)[J].Episodes,19(3):77-81.
• Ripperdan R L,Magaritz M,Kirschvink J L.1993.Carbon isotope and magnetic polarity evidence for non-depositional events within the Cambrian-Ordovician boundary section near Dayangcha,Jilin Province,China[J].Geological Magazine,130:443-452.
• Ripperdan R L,Miller J F.1995.Carbon isotope ratios from the CambrianOrdovician boundary section at Lawson Cove,Ibex area,Utah[C]//Cooper J D,Droser M L,Finney S C (eds.).Ordovician Odyssey:Short Papers for the Seventh International Symposium 382 December 2021on the Ordovician System:Pacific Section SEPM,Fullerton,California,129-132.
• Ross R J Jr,Hintze L F,Ethington R L,Miller J F,Taylor M E,Repetski J E,Sprinkle J,Guensburg T E.1997.The Ibexian,lowermost series in the North American Ordovician[J].USGS Professional Paper,1579:50.
• Runkel A C,Mackey T J,Cowan C A,Fox D L.2010.Tropical shoreline ice in the late Cambrian:implications for Earth’s climate between the Cambrian Explosion and the Great Ordovician Biodiversification Event[J].GSA Today,20(11):4-10.
• Salvador A.1994.International Stratigraphic Guide:A Guide to Stratigraphic Classification,Terminology,and Procedure.2nd Edition[M].Colorado:International Union of Geological Sciences and the Geological Society of America Boulder.
• Stouge S,Bagnoli G,McIlroy D.2017.Cambrian-Middle Ordovician platform-slope Stratigraphy,Palaeontology and Geochemistry of Western Newfoundland[M].Geological Survey of Newfoundland and Labrador,Open File 012B/0692.
• Terfelt F,Bagnoli G,Stouge S.2012.Re-evaluation of the conodont Iapetognathus and implications for the base of the Ordovician System GSSP[J].Lethaia,45:227-237.
• Wang X F,Erdtmann B D.1986.The earliest Ordovician graptolite sequence from Hunjiang,Jilin Province,China[J].Acta Geologica Sinica,3:226-236.
• Wang X F,Erdtmann B D.1987.Zonation and correlation of the earliest Ordovician graptolites from Hunjiang,Jilin province,China[J].Bulletin of the Geological Society of Denmar,35:245-257.
• Wang X F,Erdtmann B D.1992.Ordovician chronostratigraphy-A Chinese approach[M]//Webby B D,Lauries J R (eds.).Global Perspectives on Ordovician Geology.Rotterdam:Balkema A.A.,35-55.
• Wang X F,Stouge S,Chen X H,Li Z H,Wang C S,Finney S C,Zeng Q L,Zhou Z Q,Chen H M,Erdtmann B D.2009.The global stratotype section and point for the base of the Middle Ordovician Series and the Third Stage (Dapingian)[J].Episodes,32:96-112.
• Wang X F,Stouge S,Maletz J,Bagnoli G,Qi Y P,Raevskaya E,Wang C S,Yan C B.2019.Correlating the global Cambrian-Ordovician boundary:Precise comparison of the Xiaoyangqiao Section,Dayangcha,North China with the Green Point GSSP sections,Newfoundland,Canada[J].Palaeoworld,28:243-275.
• Wang X F,Stouge S,Maletz J,Bagnoli G,Qi Y P,Raevskaya E,Wang C S,Yan C B.2021.The Xiaoyangqiao Section,Dayangcha,North China:the new global Auxiliary Boundary Stratotype Section and Point(ASSP) for the base of the Ordovician System[J].Episodes 4(4):359-283.
• Wang X F,Wang C S.2001.Tremadocian (Ordovician) graptolite diversification events in China[J].Alcheringa,25:155-168.
• Wang Z H,Zhen Y Y,Bergstr?m S M,Zhang Y D,Wu R C.2018.Ordovician conodont biozonation and biostratigraphy of North China[J].Australasian Palaeontological Memoirs,51:65-79.
• Yan C B,Stouge S,Wang X F,Wang C S.2019.Upper lower Tremadocian(Lower Ordovician) conodonts from the Upper Yeli Formation of Dayancha,Jilin Province,North China[C]//Obut O T,Sennokov N V,Kipriyanova T P (eds.).13th International symposium on the Ordovician System Novosibirsk,Russia.Contributions,225-238.
• Zeballo F J,Albanesi G L,Ortega G.2005.Conodontes y graptolitos de las formaciones Alfarcito y Rupasca (Tremadociano) en elárea de Alfarcito,Tilcara,Cordillera Oriental de Jujuy,Argentina Parte 2:Paleontología sistemática[J].Ameghiniana,42(1):47-66.
• Zhang J M,Chen J Y.1986.Lithofacies sequence[M]//Chen J Y (ed.).Aspects of the Cambrian-Ordovician Boundary in Dayangcha,China.Beijing:China Prospect Publishing House,15-34.
• Zhang J M,Wang H F,Li G X,Chen J Y.1996.Redescription of the Dayancha section as a candidate for the Global Cambrian-Ordovician Boundary Stratotype,Jilin Province,China[J].Journal of Stratigraphy,20(2):81-103.(in Chinese,with English abstract)
• Zhang Y D,Erdtmann B D.2004.Tremadocian (Ordovician) biostratigraphy and graptolites at Dayangcha (Baishan,Jilin,NE China)[J].Pal?ontologische Zeitschrift,78:323-354.
• Zhen Y Y,Percival I G,Webby B D.2017.Discovery of Iapetognathus fauna from far western New South Wales:towards a more precisely defined Cambrian-Ordovician boundary in Australia[J].Australia Journal of Earth Sciences,64(4):487-496.
• Zhou Z Y,Wang Z H,Zhang J M.1984.Cambrian-Ordovician boundary and the proposed candidates for stratotype in North and Northeastern China[M]//Academia Sinica,Nanjing Institute of Geology and Palaeontology (ed.).Cambrian-Ordovician Boundary (2).Hefei:Anhui Science and Technology Publishing House,1-62.