中文摘要：

轮南古潜山轮古7井区以东地区奥陶系碳酸盐岩遭受多期次的地质构造、岩溶作用及充填改造作用,岩溶缝洞系统发育,岩溶储层主要发育在一间房组、鹰山组地层内,垂向上发育在潜山面以下（200~300m）范围内,储层类型分为裂缝型、孔洞型、裂缝-孔洞型、洞穴型岩溶储层。通过采集28个岩溶充填物样品进行碳氧同位素地球化学分析,研究了缝洞充填物的充填期次及充填环境特征。分析表明,轮古7井区以东奥陶系碳酸盐岩古岩溶缝洞系统充填物的δ13C和δ18 O值的变化范围较大,δ13CPDB值为-7.82‰~6.03‰,平均值为-1.20‰;δ^18 OPDB值为-16.13‰~-7.24‰,平均值为-10.97‰,说明该区碳酸盐岩溶蚀作用过程中受到大气降水作用明显,反映了古风化壳岩溶环境,划分了4种不同的岩溶作用与充填期次。

英文摘要：

Ordovician carbonate in buried hill of the east area of Lungu7 is subjected to multiple phases of tectonism,karstification,and filling re-working.Therefore the karst fracture-cave system is developed in this area.Karst reservoirs are mainly developed in Yijianfang Formation and Yingshan Formation in a range of 200-300 munder the surface.Reservoir types include fracture,hole,fracture-hole and cave reservoirs.The categories of reservoir space are dominated by cavity,corrosion crack and corrosion hole.The karst seam-hole system has obvious vertical zoning characteristics divided into surface karst belt,vertical infiltration dissolution belt,runoff dissolution,and the undercurrent dissolution.This paper executes geochemical analysis of carbon and oxygen isotopes on 28 karst filling samples to evaluate the filled periods and filled environment.The result shows that there is great variation ofδ13 C（6.03‰ to-7.82‰）andδ18 O（-7.24‰to-16.13‰）,the average value is-1.20‰and-10.97‰respectively.The result indicates that the carbonate karst erosion process is affected by atmospheric precipitation,and also implies the karst environment of ancient weathering crust and four kinds of karstification and filling periods.