中文摘要：

对河北宽城地区中元古代高于庄组碳酸盐岩的碳氧同位素进行了测定和原始性验证,表明其原始组分保存良好。δ13C、δ18O值分布范围和平均值分别为-5.03‰～0.07‰、-9.92‰～-4.12‰和-0.90‰、-6.58‰,整体上稍低于前人测定的天津蓟县剖面和北京十三陵剖面数据。分析认为：研究区δ13C值主要受有机碳氧化与有机碳的埋藏速率因素影响,有机碳的埋藏速率与蓝绿藻等生物数量关系密切,藻类繁盛的时期一般都具有较高的δ13C值,藻类稀少的时期则具有较低的δ13C值。在浅水潮坪环境中,δ13C值与海平面的变化呈正相关关系;研究区δ18O值则主要受海平面变化影响,与之呈负相关关系;研究区古盐度Z值主要介于120～125之间,相关性分析表明Z值不仅反映氧同位素组成,也反映了碳同位素组成,δ18O和δ13C均与沉积介质的盐度有关,其变化趋势是盐度越大,其δ值越高。

英文摘要：

C-O isotopic analysis of carbonate sampled from the Mesoproterozoic Gaoyuzhuang Formation in the Kuancheng Area,Hebei Province,demonstrates that the original components of the carbonate have been well preserved.δ13C and δ18O ranges from-5.03‰～0.07‰ and-9.92‰～-4.12‰,respectively,with averages of-0.90‰ and-6.58‰,all of which are lower than those of Jixian section in Tianjin and Ming Tombs in Beijing by previous workers.The results show that the δ13C value in the studying area is mainly influenced by the oxidation degree and the buried rate of organic carbon,as well as the quantity of the blue green microalgae.During the peak period of blue green microalgae,δ13C value was high;during the scarcity period,δ13C was low.There is a positive correlation between the δ13C profile and sea level change in tidal flat environments.The δ18O values in the studying area are relevant to sea level change,and there is a negative correlation of them.Z value of salinity in the area ranges from 120 to 125.Correlation analysis suggests that the Z value can reflect not only O isotopic composition but also C.In addition,δ13C and δ18O is closely related to the salinity of sedimentary medium,the bigger the salinity,the higher the δ values.