塔里木盆地奥陶系碳酸盐岩碳氧稳定同位素地球化学特征  

Geochemical characteristics of carbon,oxygen stable isotopes in the Lower-Middle Ordovician carbonate rock in Tazhong and Bachu,Tarim Basin,China

作　　者：王安甲[1] 初广震[1] 黄文辉[1] 王旭[1] 

机构地区：[1]中国地质大学海相储层演化与油气富集机理教育部重点实验室,北京100083

出　　处：《成都理工大学学报（自然科学版）》2008年第6期700-704,共5页Journal of Chengdu University of Technology: Science & Technology Edition

基　　金：国家重点基础研究发展规划项目(2005CB422103)

摘　　要：中-下奥陶统碳酸盐岩储层是塔里木盆地塔中地区的主要油气产层。利用碳氧稳定同位素的分布特征和变化规律,可分析影响碳酸盐岩沉积环境和成岩作用的因素。中-下奥陶统的碳酸盐岩可在垂向上把δ13C和δ18O值的变化趋势划分为三段,二者的变化趋势是一致的。中-上奥陶统岩层碳氧稳定同位素比值明显下降,证明中-下奥陶统经历过一次短暂的抬升暴露和随后的大面积海水加深淹没事件。海水淹没时期,大量C转到海水之中,海水中沉淀出的碳酸盐岩的δ13C值相对较低。The carbonate rock reservoirs of the Lower-Middle Ordovician in Tazhong of Tarim Basin are the main oil and gas pays. Through analyzing the variation regularity of carbon and oxygen stable isotopes in carbonate rocks,the authors can acquire the factors that dominate the depositional setting and diagenesis of the carbonate rocks. The trend of the δ^13 C and δ^18 O vertical values changes of the carbonate rock reservoir in the research area can be classified into three sections. Both have the same change trend. The δ13 C and δ^18 O values of the Upper-Middle Ordovician carbonate rocks are apparently becoming lower. This approves that there exactly exist a short uplift, erosion and the following large-scale marine transgression during the Upper-Lower Ordovician. During this time, much 12^C migrates into the sea. Accordingly, the carbonate rocks deposited from this marine setting have lower 13^C values.

关 键 词：塔里木盆地 奥陶系 碳酸盐岩 碳同位素 氧同位素 地球化学特征 

分 类 号：P632.7[天文地球—地质矿产勘探]