中文摘要：

研究了若尔盖铀矿田中灰岩、硅灰岩及方解石脉的碳氧同位素组成，结果表明产于地层中的灰岩、硅灰岩及方解石脉的占δ13C值为-1．48‰～3．18‰，平均为1．51‰，为海洋沉积碳酸盐岩的碳同位素组成特征；占δ18O值为-12．81‰-3．71‰，平均为-9．92‰，在铀矿田中占δ18O值最高。与成矿作用关系最为密切的含矿方解石脉占δ13C值为-2．78‰-4．81‰，平均为-3．93‰，明显表现为地幔来源的特点；δ18O值为-13．14‰-15．05‰，平均为-13．87‰，其值在铀矿田中介于地层中岩石（脉）与矿区方解石脉之间。矿区方解石脉的占δ13C值为-3．53‰～-6．35‰，平均为-4．93‰，与含矿方解石脉的碳同位素组成相近，表明其亦是成矿作用的产物；占δ18O值为-16．00‰-24．75‰，平均为-19．36‰，在铀矿田中占δ18O值最低，明显表现为深部来源特征。综合若尔盖铀矿田的碳氧同位素组成特征，暗示其成矿流体应当来源于地幔。

英文摘要：

This paper deals with δ13C and δ18O values for limestone, siliceous limestone and vein calcite from the ZoigE uranium ore field. The δ13C values vary from -1.48‰ to 3.18‰ with an average value of 1.51‰ characteristic of marine sedimentary carbonate and the δ18O values from -12.81‰ to -3.71‰ with an average value of -9.92‰. The δ13C values of the ore-bearing vein calcite range from -2.78‰ to -4.81‰ with an average of -3.93‰ characteristic of mantle-derived carbon and the δ18O values range from -13.14‰ to -15.05‰ with an average value of-13.87‰ ranging between the dyke and vein calcite in the uranium ore field. The δ13C values vary from -3.53‰ to -6.35‰ with an average of-4.93%o which are the same as the δ13C values for ore-bearing vein calcites, showing that it is also the product of mineralization. And the δ18O values vary from -16.00‰ to -24.75‰ with an average of -19.36‰ which is the lowest in the uranium ore field and is characteristic of deep sources. In a word, δ13C and δ18O values for carbonate from the Zoige uranium ore field indicate that the ore fluids should be mantle-derived.