Carbon and oxygen isotopic composition of lacustrine carbonate rocks of the Lower-Middle Jurassic in NE part of central Sichuan Province and their palaeoenvironmental significance
Zhang Wei1, Li Zhiwu1, Feng Feng2, Zhai Zhonghua2, Sun Wei1, Tang Cong1, Ding Yi1, Liu Shugen1
1 State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation，Chengdu University of Technology，Chengdu610059，Sichuan; 2 Central Sichuan Oil and Gas District，PetroChina Southwest Oil and Gas Field Company，Suining629000，Sichuan
Based on the drilling core observation and petrographic characteristics，this paper analyzed the carbon and oxygen isotopic composition of the typical drilling carbonate samples from the Ziliujing and Lianggaoshan Formations of Lower-Middle Jurassic in Longgang area，NE part of central Sichuan Province.The test result of more than 40 samples shows that the δ13C values are between-1.24‰ and 4.59‰(in addition to a negative value), and the δ18O values are between -15.7‰ and -9.83‰.Compared with the isotopic values of marine and continental carbonate rocks，the ancient lake is characterized by inland open lake without obviously seawater intrusion during the Ziliujing and Lianggaoshan Ages.The widespread existence of carbon isotope positive excursion in the Lower-Middle Jurassic might be caused by the improved lake primary productivity.The petrographic and isotopic change indicates that the ancient lake level had gone through two main cycles and six sub-cycles.The overall lake level might be lower in turn during the depositional periods of Dongyuemiao Member，Dayisan sub-Member of Ziliujing Formation，Lianggaoshan Formation and Maanshan Member，while the lake primary productivity may be decreased gradually during the depositional period of Dayisan sub-Member，Dongyuemiao Member，Dayi sub-Member of Ziliujing Formation，Lianggaoshan Formation and Maanshan Member.
Zhang Wei,Li Zhiwu,Feng Feng et al. Carbon and oxygen isotopic composition of lacustrine carbonate rocks of the Lower-Middle Jurassic in NE part of central Sichuan Province and their palaeoenvironmental significance[J]. JOPC, 2013, 15(2): 247-260.
郭正吾，邓康龄，韩永辉，等.1996.四川盆地形成与演化［M］.北京: 地质出版社，114-124.黄其胜.2001.四川盆地北缘达县、开县一带早侏罗世珍珠冲植物群及其古环境［J］.地球科学，26(3)：221-228.刘传联，赵泉鸿，汪品先.2001.湖相碳酸盐氧碳同位素的相关性与生油古湖泊类型［J］.地球化学，30(4):363-367.刘树根，李智武，孙玮，等.2011.四川含油气叠合盆地基本特征［J］.地质科学，46(1):233-257.王全伟，梁斌，阚泽忠.2006.四川盆地下侏罗统自流井组湖相碳酸盐岩的碳、氧同位素特征及其古湖泊学意义［J］.矿物岩石，26(2):87-91.王永标，徐海军.2001.四川盆地侏罗纪至早白垩世沉积旋回与构造隆升的关系［J］.地球科学，26(3):241-264.Alonso-Zarza A M.2003.Palaeoenvironmental significance of palustrine carbonates and calcretes in the geological record［J］.Earth-Science Reviews，60: 261-298.Bolhar R，Kranendonk R J.2007.A non-marine depositional setting for the northern Fortescue Group，Pilbara Craton，inferred from trace element geochemistry of stromatolitic carbonates［J］.Precambrian Research，155: 229-250.Carmala N，Garzione，David L.2004.Carbonate oxygen isotope paleoaltimetry: Evaluating the effect of diagenesis on paleoelevation estimates for the Tibetan plateau［J］.Palaeogeography，Palaeoclimatology，Palaeoecology，212: 119-140.Cerling T E，Quade J.1993.Stable Carbon and Oxygen Isotopes in Soil Carbonates［M］.In: Climate Change in Continental Isotopic Records.American Geophysical Union，Geophysical Monograph，78: 217-231.Craig H.1965.The measurement of oxygen isotope paleotemperatures［M］.In: Tongiorgi E(ed).Stable Isotopes in Oceanographic Studies and Paleotemperatures.Consiglio Nazionale delle Richerche，Laboratorio di Geologia Nucleare，Pisa，1-24.Emrich K，Ehhalt D H，Vogel J C.1970.Carbon isotope fractionation during the precipitation of calcium carbonate［J］.Earth and Planetary Science Letters，8: 363-371.Gabriel J B，Andrew L D，Brenda B B.2008.Paleoenvironmental isotope geochemistry and a genesis of lacustrine and palustrine carbonates，Flagstaff Formation，Central Utah，U.S.A［J］.Journal of Sedimentary Research，78：162-174.Ghosh P，Bhattacharya S K，Chakrabarti A.2001.Stable isotopic studies of microbial carbonates from Talchir sediments of east-central India［J］.Current Science，80: 1326-1330.Gomez F J，Ogle N，Astini R A， et al.2007.Paleoenvironmental and carbon oxygen isotope record of Middle Cambrian carbonates(La Laja Formation)in the Argentine Precordillera［J］.Journal of Sedimentary Research，77: 826-842.Hoefs J.2009.Stable Isotope Geochemistry (6th Edition)［M］.Berlin: Springer-Verlag.Li H C,Ku T L.1997. δ13C-δ18O covariance as a paleohydrological indicator for closed-basin lakes ［J］. Palaeogeography,Palaeoclimatology,Palaeoecology,133:69-80.Li H C,Bischoff J L,Ku T L, et al. 2000.Climate variability in east central California during the past 1000 years:High-resolution geochemical and isotopic records from Owens Lake sediments ［J］. Quaternary Research,54:189-197.Longinelli A，Edmond J M.1983.Isotope geochemistry of the Amazon Basin: A reconnaissance［J］.Journal of Geophysical Research，88: 3703-3717.McKenzie J A.1985.Carbon Isotopes and Productivity in the Lacustrine and Marine Environment［M］.In: Stumm W(ed).Chemical Processes in Lakes.New York: Wiley，99-118.Milliman J D.1974.Recent Sedimentary Carbonates: Marine Carbonates［M］. New York:Springer.Nelson J A，Licht K，Yansa C， et al.2010.Climate-related cyclic deposition of carbonate and organic matter in Holocene lacustrine sediment，Lower Michigan，USA［J］.Journal of Palaeolimnology，44: 1-13.Oana S，Deevey E S.1960.Carbon 13 in lake waters and its possible bearing on paleolimnology［J］.Am.J.Sci.，258A: 253-272.Patterson W P，Walter L M.1994.Depletion of13C in seawater ΣCO2 on modern carbonate platforms: Significance for the carbon isotopic record of carbonates［J］.Geology，22: 885-888.Platt N H.1989.Lacustrine carbonates and pedogenesis: Sedimentology and origin of palustrine deposits from the Early Cretaceous Rupelo Formation，W Cameros Basin，N Spain［J］.Sedimentology，36: 665-684.Shichi K，Kawamuro K，Takahara H， et al.2007.Climate and vegetation changes around Lake Baikal during the last 350，000 years［J］.Palaeogeography，Palaeoclimatology，Palaeoecology，248: 357-375.Talbot M R.1990.A review of the palaeohydrological interpretation of carbon and oxygen stable isotopic ratios in primary carbonates［J］.Chemical Geology(Isotope Geosciences Section)，80:261-279.Talbot M R.1994.Paleohydrology of the late Miocene Ridge basin lake，California［J］.Geological Society of America Bulletin，106:1121-1129.Talbot M R，Kelts K.1990.Paleolimnological Signatures from Carbon and Oxygen Isotopic Ratios in Carbonates from Organic Carbon-rich Lacustrine Sediments［M］.Katz B J(ed).Lacustrine Basin Exploration-Case Studies and modern Analogs，AAPG Memoir 1990，50: 99-112.Veizer J，Ala D，Azmy K. et al.1999.87Sr/86Sr，δ13C and δ18O evolution of Phanerozoic seawater［J］.Chemical Geology，161:59-88.Vonhof H B，Wesselingh F P，Kaandorp R J G, et al.2003.Paleogeography of Miocene Western Amazonia: Isotopic composition of molluscan shells constrains the influence of marine incursions［J］.Geological Society of America Bulletin，115:983-993.Zachos J，Pagini M，Sloan L. et al.2001.Trends，rhythms，and aberrations in global climate 65 Ma to present［J］.Science，292:686-693.
