Oxygen and carbon isotopic records of the Late Triassic Carnian pluvial event deposits in northwestern Sichuan Province
Wang Yanyan1, Zhang Biao2, Shi Zhiqiang2, Yi Haisheng2
1 College of Materials and Chemistry ＆ Chemical Engineering，Chengdu University of Technology，Chengdu 610059，Sichuan 2 Institute of Sedimentary Geology，Chengdu University of Technology，Chengdu 610059，Sichuan
Abstract Distinct lithological mutations from grey ooides，sponge reef limestone to grayish black shale，and then argillaceous siltstone are distinguished from the Upper Triassic Carnian marine sediments in the Mianzhu and Anxian counties in northwestern Sichuan Province，which is very similar to the sediments representing the Carnian pluvial event in western Tethys area.The stable oxygen and carbon isotopic compositions of the Carnian fossils of foraminifer，bivalve and brachiopodous shells and plant leaves are analyzed using laser micro-sampling technique.The analysis results indicate the slightly lowerδ18O values and remarkable lower δ13C values of the Upper Carnian than those of the Lower Carnian.Its believed that the isotopic compositions reflect that fresh water input into the Paleotethys ocean.We suggest that the Carnian pluvial event severely affected the deposits in the eastern Tethys area.The freshwater input in the humid conditions is one of the causes that triggered the periodic deaths and finally disappearing of the sponge reefs in the study area.
About author: Wang Yanyan，born in 1976，is an engineer，and is engaged in teaching and researches of geochemistry.E-mail:yy_wang320@163.com.
Cite this article:
Wang Yanyan,Zhang Biao,Shi Zhiqiang et al. Oxygen and carbon isotopic records of the Late Triassic Carnian pluvial event deposits in northwestern Sichuan Province[J]. JOURNAL OF PALAEOGEOGRAPHY, 2012, 14(3): 375-382.
Wang Yanyan,Zhang Biao,Shi Zhiqiang et al. Oxygen and carbon isotopic records of the Late Triassic Carnian pluvial event deposits in northwestern Sichuan Province[J]. JOPC, 2012, 14(3): 375-382.
何道清.2003.碳酸盐岩碳、氧同位素分析激光微取样技术［J］.西南石油学院学报，25(1):12-15. 强子同，马德岩，顾大镛，等.1996.激光显微取样稳定同位素分析［J］.天然气工业，16（6）:86-89. 时志强，欧莉华，罗凤姿，等.2009.晚三叠世卡尼期黑色页岩事件在龙门山地区的沉积学和古生物学响应［J］.古地理学报，11（4）:375-383. 时志强，钱利军，曾德勇，等.2010a.晚三叠世卡尼期碳酸盐生产危机在东特提斯地区的地质记录［J］.地质论评，56（3）:321-328. 时志强，钱利军，熊兆军，等.2010b.中国西南部地区卡尼期危机及其形成原因探讨［J］.矿物岩石地球化学通报，29（3）:227-232. 时志强，张华，曾德勇，等.2010c.龙门山前缘上三叠统卡尼阶特征及其古环境、古气候意义［J］.成都理工大学学报(自然科学版)，37(4):425-431. 吴熙纯.1990.川西北晚三叠世的灯海绵动物群［J］.古生物学报，29(3):349-365. 吴熙纯.2009.川西北晚三叠世卡尼期硅质海绵礁—鲕滩组合的沉积相分析［J］.古地理学报，11（2）:125-142. 杨荣军，刘树根，吴熙纯，等.2008.龙门山前缘上三叠统马鞍塘组沉积分布特征及其控制因素［J］.成都理工大学学报(自然科学版)，35(4):455-462. Balog A.1999.Climate-controlled early dolomite，Late Triassic cyclic platform carbonates，Hungary［J］.Journal of Sedimentary Research，69: 267-282. Baud A，Magaritz L M，Holser W T.1989.Permian-Triassic of the Tethys: Carbon isotope studies［J］.Geologische Rundschau，78(2):649-677. Colombi C E，Parrish J T.2008.Late Triassic environmental evolution in southwestern Pangea: Plant taphonomy of the Ischigualasto Formation［J］.Palaios.，23:778-795. Holser W T，Schnlaub H P，Attrep J， et al. 1989.A unique geochemical record at the Permian/Triassic boundary［J］.Nature，337:39-44. Hornung T，Brandner R.2005.Biostratigraphy of the Reingraben Turnover(Hallstatt Facies Belt): Local black shale events controlled by the regional tectonics，climatic change and plate tectonics［J］.Facies，51: 460-479. Hornung T，Brandner R，Leopold K.2007a. Multistratigraphic constraints on the NW Tethyan “Carnian crisis”［C］. In: Lucas S G，Spielmann J A(eds.).The Global Triassic: New Mexico Museum of Natural History and Science Bulletin，41: 59-67. Hornung T，Krystyn L，Brandner R.2007b. A Tethys-wide mid-Carnian(Upper Triassic)carbonate productivity decline: Evidence for the Alpine Reingraben Event from Spiti(Indian Himalaya)？［J］.Journal of Asian Earth Sciences，30: 285-302. Hornung T，Spatzenegger A，Joachimski M M.2007c.Multistratigraphy of condensed ammonoid beds of the Rappoltstein(Berchtesgaden，Southern Germany): Unravelling palaeo-environmental conditions on ‘Hallstatt deep swells during the Reingraben Event(late Lower Carnian)［J］.Facies，53:267-292. Immenhauser A，Schlager W，Burns S J， et al. 1999.Late Aptian to late Albian sea-level xuctuations constrained by geochemical and biological evidence(Nahr Umr Formation，Oman)［J］.Journal of Sedimentary Research, 69(2):434-446. Keim L，Spotl C，Brandner R.2006.The aftermath of the Carnian carbonate platform demise: A basinal perspective(Dolomites，Southern Alps)［J］.Sedimentology，53: 361-386. Mutti M，Weissert H.1995.Triassic monsoonal climate and its signature in Ladinian-Carnian carbonate platforms(Southern Alps，Italy)［J］.Journal of Sedimentary Research，65(3):357-367. Parrish J T.1993.Climate of the supercontinent Pangea［J］.Journal of Geology，101:215-233. Parrish J T，Ziegler A M，Scotese C R.1982.Rainfall patterns and the distribution of coals and evaporites in the Mesozoic and Cenozoic［J］.Palaeogeography，Palaeoclimatology，Palaeoecology, 40:67-101. Preto N，Kustatscher E，Wignall P B.2010.Triassic climates: State of the art and perspectives［J］.Palaeogeography，Palaeoclimatology，Palaeoecology，290: 1-10. Rigo M，Preto N，Roghi G， et al.2007.A rise in the Carbonate Compensation Depth of western Tethys in the Carnian(Late Triassic): Deep-water evidence for the Carnian Pluvial Event［J］.Palaeogeography，Palaeoclimatology，Palaeoecology, 246: 188-205. Robinson P L.1973.Paleoclimatology and continental Drift［M］.In: Tarling D H，Runcorn S K(eds). Implications of Continental Drift to the Earth Sciences.London: Academic Press，449-476. Roghi G，Gianolla P，Minarelli L， et al. 2010.Palynological correlation of Carnian humid pulses throughout western Tethys［J］.Palaeogeography，Palaeoclimatology，Palaeoecology，290: 89-106. Schlager W，Schllnberger W.1974.Das prinzip stratigraphischer Wenden in der Schichtfolge der Nrdlichen Kalkalpen,Mitteilungen［J］.sterreichische Geologische Gesellschaft, 66-67: 165-193. Simms M J，Ruffell A H.1989.Synchroneity of climatic change and extinctions in the Late Triassic［J］.Geology，17:265-268. Simms M J，Ruffell A H.1990.Climatic and biotic change in the Late Triassic［J］.Journal of the Geological Society of London，147:321-327. Simms M J，Ruffel A H，Johnson L A.1995.Biotic and climatic Changes in the Carnian(Triassic)of Europe and adjacent areas［C］.In: Fraser N C，Sues H D(eds). In the Shadow of the Dinosaurs: Early Mesozoic Tetrapods.London: Cambridge University Press，352-365. Wang P X.2009.Global monsoon in a geological perspective［J］.Chinese Science Bulletin，54(7):1113-1136.
