峡东地区早奥陶世C同位素异常及其成因  

Lower Ordovician carbon isotope excursion in the eastern Yangtze Gorges area and its genetic analysis

作　　者：张保民[1] 陈孝红[1] 周鹏[1] 李志宏[1] 彭中勤[1] 曾雄伟[1] ZHANG Baomin;CHEN Xiaohong;ZHOU Peng;LI Zhihong;PENG Zhongqin;ZENG Xiongwei(Wuhan Center of Geological Survey, CGS, Wuhan 430223 , Hubei, China)

机构地区：[1]中国地质调查局武汉地质调查中心,湖北武汉430223

出　　处：《地质通报》2017年第5期792-799,共8页Geological Bulletin of China

基　　金：中国地质调查局项目<华南中部震旦纪-志留纪地层格架;岩相古地理与成矿关系>(编号:1212011121103)和<湖北1:5万分乡;莲沱;三斗坪;宜昌市幅区域地质调查>(编号:1212010710715)

摘　　要：以宜昌黄花场奥陶系剖面为研究对象,开展峡东地区早奥陶世C同位素研究,建立了峡东地区早奥陶世C同位素曲线,并识别出可全球对比的2次正漂移(C1,C3)和2次负漂移(C2,C4)。通过分析峡东地区沉积相序列及海平面变化特征,发现峡东地区C同位素变化曲线与海平面波动曲线一致,表明峡东地区C同位素的变化主要受控于海平面的波动。The carbon stable isotope curve was constructed in this paper from the Huanghuachang sections of Lower Ordovician inthe eastern Yangtze Gorges area.δ13C data demonstrate that there existed twoδ13C positive excursions(C1,C3)and two negativeexcursions(C2,C4),all of which are comparable in the global scale.Based on the sedimentary sequence characteristics of Lower Or?dovician in the eastern Yangtze Gorges area,the authors observed that the curve ofδ13C is coincident with the curve of the regionalsea-level fluctuations.This study indicates that the geochemistry as well as the sequences was well controlled by the sea level changes.

关 键 词：C 同位素 海平面变化 早奥陶世 峡东地区 

分 类 号：P534.42[天文地球—古生物学与地层学] P597.2[天文地球—地质学]