Sedimentary characteristics of the Upper Ordovician Wenchang and Yankou Formations in northwestern Zhejiang Province
Liu Xiao1,2, Zhang Yuandong1, Zhou Chuanming1
1 State Key Laboratory of Palaeobiology and Stratigraphy，Nanjing Institute of Geology and Palaeontology， Chinese Academy of Sciences，Nanjing 210008，Jiangsu 2 Research Institute of Petroleum Exploration and Development，East China Company，SINOPEC，Nanjing 210011，Jiangsu
Abstract：Based on new collections of fossils from the Upper Ordovician Wenchang，Yankou and Anji Formations in northwestern Zhejiang Province，southeastern China，especially those significant graptolites，the Wenchang Formation is considered to be equivalent to the Yankou Formation，and is largely of Hirnantian Age.In Hirnantian Age，the Gondwana ice sheet，centered in the North Africa，reached its maximum，as evidenced by that more and more glacial deposits(tillites or diamictites)of the age have been reported across the world.The Wenchang and Yankou Formations yield well-developed conglomerates，which are unique in South China and might be related with the glaciation event.Regarding the origination of the conglomerates，there have been some debates and viewpoints from different perspectives.Based on sedimentary studies，these conglomerates display different sedimentary characters and mechanisms among localities and sections in the region.They represent several types of channel depositions in shallow water.A detailed regional lithofacies study of the Wenchang and Yankou Formations in northwestern Zhejiang Province indicates that a Zhe-Wan Basin was developed in the Hirnantian Age，with Cathaysian Land located to its southeast and served as the clastic source.The basin becomes deeper northwestwardly，following the palaeogeographic pattern of pre-Hirnantian.Petrological analysis of the sandstones in the Wenchang and Yankou Formations displays a low compositional maturity along with a low textural maturity，and a provenance of recycled orogenic belt，which indicate a probable sustaining uplift of the Cathaysian Land.The regressional sequence recognized in the Wenchang and Yankou Formations in northwestern Zhejiang Province can be well correlated with that of other continents or regions，such as North Africa，Middle East，U.K.，Sweden and Czech etc.
Liu Xiao,Zhang Yuandong,Zhou Chuanming. Sedimentary characteristics of the Upper Ordovician Wenchang and Yankou Formations in northwestern Zhejiang Province[J]. JOPC, 2012, 14(1): 101-116.
安徽省地质矿产局.1987.安徽省区域地质志［M］.北京：地质出版社，50-66. 蔡进功，李从先.1990.浙西桐庐县桐君山下志留系安吉组风暴沉积［J］.同济大学学报，18（3）:363-372. 陈旭，樊隽轩，Melchin M J，等.2004.华南奥陶纪末笔石灭绝及幸存的进程与机制［C］.见：戎嘉余，方宗杰.生物大灭绝与复苏—来自华南古生代和三叠纪的证据.安徽合肥：中国科技大学出版社，9-54. 陈旭，戎嘉余，樊隽轩，等.2006.奥陶系上统赫南特阶全球层型剖面和点位的建立［J］.地层学杂志，30（4）:289-305. 陈旭，戎嘉余，Rowley D B,等.1995.对华南早古生代板溪洋的质疑［J］.地质论评，41（5）：389-400. 范代读，李从先，蔡进功，等.2003.浙江桐庐晚奥陶世晚期沉积层序和沉积环境分析［J］.沉积学报，21（2）:247-254. 冯洪真，俞剑华，方一亭，等.1993.五峰期上扬子海古盐度分析［J］.地层学杂志，17（3）:179-185. 冯增昭，彭勇民，金振奎，等.2001.中国南方寒武纪和奥陶纪岩相古地理［M］.北京:地质出版社，1-221. 冯增昭，彭勇民，金振奎，等.2004.中国晚奥陶世岩相古地理［J］.古地理学报，6(2):127-139. 何幼斌，高振中，李建明，等.1998.浙江桐庐晚奥陶世内潮汐沉积［J］.沉积学报，16（1）:1-7. 何幼斌，高振中，李建明.1999.浙江桐庐上奥陶统堰口组岩石特征及沉积环境分析［J］.古地理学报，1（3）:65-72. 李积金.1984.皖南晚奥陶世地层及其与国内外的对比—中国科学院南京地质古生物研究所集刊，第20号［M］.北京：科学出版社，113-144. 梁鼎新，陈联儿.1990.浙西和皖南地区显生宙沉积大地构造演化［J］.华东地质学院学报，13（4）:84-92. 罗璋，葛凡凡.1982.浙江省上震旦统、下古生界沉积环境及相分析［J］.浙江石油地质，（1）:12-17. 钱家驹.1987.浙江西部晚奥陶世五峰期沉积及奥陶系—志留系分界［J］.地质学报，（2）:101-112. 戎嘉余，詹仁斌，许红根，等.2010.华夏古陆于奥陶—志留纪之交的扩展证据和机制探索［J］.中国科学（D辑），40(1):1-17. 戎嘉余，陈旭.1987.华南晚奥陶世动物群分异以及生物相、岩相分布模式［J］.古生物学报，26（5）:508-526. 戎嘉余，詹仁斌.1999.华南奥陶—志留纪腕足动物群的更替——兼论奥陶纪末冰川活动的影响［J］.现代地质，13（4）:390-394. 戎嘉余.1984.上扬子区晚奥陶世海退的生态地层与冰川活动的影响［J］.地层学杂志，8（1）:19-30. 盛莘夫.1974.中国奥陶系的划分与对比［M］.北京：地质出版社，58-65. 汪隆武，许红根，齐岩辛，等.2004.浙赣交界地区上奥陶统红家坞组（O3h）［J］.地层学杂志，28（1）:52-58. 吴浩若.2005.下扬子区加里东期构造古地理问题［J］.古地理学报，7（2）:243-248. 夏邦栋，吕洪波.1988.苏、浙、皖地区沉积—大地构造演化［J］.地质学报，（4）:302-310. 杨达铨.1983.浙江西北部上奥陶统上部的笔石［J］.古生物学报，22（6）:597-605. 余素玉，张平.1986.浙江临安上奥陶统浊流沉积中的黏土矿物［J］.矿物岩石，6（3）:55-64. 俞国华.1996.浙江省岩石地层［M］.湖北武汉：中国地质大学出版社，55-66. 俞月德.1985.浙西皖南地区奥陶纪晚世中晚期古地理环境及其沉积特征初探［J］.浙江石油地质，（1）:31-41. 赵澄林，朱筱敏.2001.沉积岩石学［M］.北京：石油工业出版社，276-290. 浙江省地质矿产局.1989.浙江省区域地质志［M］.北京：地质出版社，62-75. 浙江省区测队.1965.1：20万建德幅区域矿产地质调查报告［M］.浙江杭州：浙江省地质局，28-39. 浙江省区测队.1967.1：20万临安幅区域矿产地质调查报告［M］.浙江杭州：浙江省地质局，29-60. 浙江省区域地层编写组.1979.华东地区区域地层表浙江省分册［M］.北京：地质出版社，33-67. 朱洪发，张渝昌，秦德余，等.1990.论浙皖赣闽地区早古生代盆地沉积特征及其构造环境［J］.石油实验地质，12（2）:121-134. Armstrong H A，Turner B R，Makhlouf I M， et al. 2005.Origin，sequence stratigraphy and depositional environment of an Upper Ordovician(Hirnantian)deglacial black shale，Jordan［J］.Palaeogeography，Palaeoclimatology, Palaeoecology，220:273-289. Bergstrm S M，Saltzman M M，Schmitz B.2006.First record of the Hirnantian(Upper Ordovician)δ13C excursion in the North American Midcontinent and its regional implications［J］.Geological Magazine，143(5):657-678. Berry W B N，Quinby-Hunt M S，Wilde P.1995.Impact of Late Ordovician glaciation-deglaciation on marine life［C］.In：Stanley S M(ed).Studies in Geophysics: Effects of Past Global Change on Life.Washington，D.C.:National Academy Press,34-46. Brenchley P J，Romano M，Young T P， et al. 1991.Hirnantian glaciomarine diamictites-evidence for the spread of glaciation and its effect on Upper Ordovician faunas［C］.In：Barnes C R，Williams S H(eds).Advances in Ordovician Geology.Geological Survey of Canada Paper，90-9:325-336. Brenchley P J，torch P.1989.Environmental changes in the Hirnantian(Upper Ordovician)of the Prague Basin，Czechoslovakia［J］.Geological Journal，24:165-181. Brenchley P J.2004.End Ordovician glaciation［C］.In：Webby W D，Paris F，Droser M L，et al.(eds).The Great Ordovician Biodiversification Event.New York：Columbia University Press,81-83. Brenchley P J.2006.A Late Ordovician(Hirnantian)karstic surface in submarine channel，recording glacio-eustatic sea-level changes，Meifod，central Wales［J］.Geological Journal，41:1-22. Chen X，Zhang Y D，Yu G H， et al.2007.Latest Ordovician and earliest Silurian graptolites from the northwest Zhejiang［J］.Acta Palaeontologica Sinica，46（Supplement）：77-82. Chen X.1984.Influence of the Late Ordovician glaciation on basin configuration of the Yangtze Platform in China［J］.Lethaia，17:5l-59. Dahlqvist P，Calner M.2004.Late Ordoviciam paleoceanographic changes as reflected in the Hirnantian-early Llandovery succession of Jmtland，Sweden［J］.Palaeogeography，Palaeoclimatology，Palaeoecology，210:149-64. Delabroye A，Vecoli M.2010.The end-Ordovician glaciation and the Hirnantian Stage: A global review and questions about Late Ordovician event stratigraphy［J］.Earth-Science Review，98:269-282. Díaz-Martínez E，Grahn Y.2007.Early Silurian glaciation along the western margin of Gondwana(Peru，Bolivia and northern Argentina): Palaeogeographic and geodynamic setting［J］.Palaeogeography，Palaeoclimatology，Palaeoecology，245: 62-81. Dickinson W R.1985.Interpreting provenance relations from detrital modes of sandstone［C］.In：Zuffa G G(ed).Provenance of Arenites.Dordrecbt：MATO-ASI Series，148:333-361. Dickinson W R，Suczek C A.1979.Plate tectonics and sandstone composition［J］.AAPG Bulletin，63(12):2164-2182. Dickinson W R，Valloni R.1983.Provenance of North American Phanerozoic sandstones in relation to tectonic setting［J］.Geology Society America Bulletin，94（2）:222-235. Finney S C，Berry W B N，Cooper J D， et al. 1999.Late Ordovician mass extinction： A new perspective from stratigraphic sections in central Nevada［J］.Geology，27:215-218. Ge M Y.1984.The Graptolitc Fauna of the Ordovician-Silurian Boundary section in Yuqian，Zhejiang［C］.In：Nanjing Institute of Geology and Palaeontology(ed).Stratigraphy and Palaeontology of Systemic Boundaries in China: Ordovician-Silurian Boundary(1).Ahhui Hefei：Anhui Science and Technology Publishing House.389-454. Ghienne J F.2003.Late Ordovician sedimentary environments，glacial cycles，and post-glacial transgression in the Taoudeni Basin，West Africa［J］.Palaeogeography，Palaeoclimatology，Palaeoecology，189: 117-145. Ghienne J F.2011.The late Ordovician glacial record: State of the art［C］.In: Gutiérrez-Marco J C，Rbano I，Gacía-Bellido D(eds).Ordovician of the World(proceeding volume of the 11th Symposium on the Ordovician System).Cuadernos del Museo Geominero，14.Madrid: Instituto Geologicoy Minero de Espana，13-19. Lüning S，Shahin Y M，Loydell D， et al. 2005.Anatomy of a world-class source rock: Distribution and depositional model of Silurian organic-rich shales in Jordan and implications for hydrocarbon potential［J］.AAPG Bulletin，89: 1397-1427. Mitchell，C E，torch，P，Holmden， et al. 2011.New stable isotope data and fossils from the Hirnantian Stage in Bohemia and Spain: Implications for correlation and paleoclimate［C］.In: Gutiérrez-Marco J C，Rbano I，Gacía-Bellido D(eds).Ordovician of the World(proceeding volume of the 11th Symposium on the Ordovician System).Cuadernos del Museo Geominero，14.Madrid: Instituto Geologico y Minero de Espana，371-378. Monod O，Kozlu H，Ghienne J F， et al.2003.Late Ordovician glaciation in southern Turkey［J］.Terra Nova，15: 249-257. Schnlaub H P，Ferretti A， et al.2011. The Late Ordovician glacial event in the Carnic Alps(Austria)［C］.In: Gutiérrez-Marco J C，Rbano I，Gacía-Bellido D(eds).Ordovician of the World(proceeding volume of the 11th Symposium on the Ordovician System).Cuadernos del Museo Geominero，14.Madrid: Instituto Geologico y Minero de Espana，515-526. torch P.2006.Facies development，depositional settings and sequence stratigraphy across the Ordovician-Silurian boundary: A new perspective from the Barrandian area of the Czech Republic［J］.Geological Magazine，41: 163-192. Sutcliffe O E，Dowdeswell J A，Whittington R J， et al. 2000.Calibrating the Late Ordovician glaciation and mass extinction by the eccentricity cycles of Earth s orbit［J］.Geology，28:967-970. Turner B R，Mahklouf I M，Armstrong H A.2005.Late Ordovician(Ashgillian)glacial deposits in southern Jordan［J］.Sedimentary Geology，181: 73-91. Zhang T S，Kershaw S，Wan Y， et al. 2000.Geochemical and facies evidence for palaeoenvironmental change during the Late Ordovician Hirnantian glaciation in South Sichuan Province［J］. China Globe Planet Change，24:133-152. Zhang Y D，Chen X，Yu G H， et al.2007.Ordovician and Silurian System of Northwest Zhejiang and Northeast Jiangxi，SE China［M］.Anhui Hefei：University of Science and Technology of China Press，1-189.
