碳酸盐岩缝洞型输导体输导性能定量表征与评价

Carbonate hydrocarbon has become important part of succeed hydrocarbon resources in China, and the fracture-cavity reservoir is the main type of it. Quantitative characterization of the fracture-cavity carrier system can help us to identify its hydrocarbon accumulation and enrichment regularity. The macro-scale research, including seismic characteristic etc., can describe the outline of fracture-cavity carrier system, but can’t depict its strong heterogeneity in detail; the micro-scale research, like microscopic study etc., can recognize petrological characteristics and diagenetic process, but has weakly ability to characterize regularity of the fracture-cavity carrier properties; while the medium-scale research can use core samples, well logging data and dynamic data, and can evaluate the fracture-cavity carrier effective poroperm properties, recognize its connectivity, and quantitative characterization of the fracture-cavity carrier properties. This project restrained by the macro- and micro-scale research results, mainly using well logging and mineral testing data, analyze the cavern filling degree and the effective permeability performance of different fillings, and recognize the effective physical properties of fracture-cavity carrier on medium scale; secondly combined with production dynamic data of fracture-cavity reservoir, analyze its fluid connectivity; then choose the appropriate parameter-combination to built the method to quantitative characterize and evaluate the carrier properties of fracture-cavity carriers; finally combined with the practical production data of oilfields, the results and knowledge of this research will be checked.

碳酸盐岩油气已成为我国重要的油气资源接替领域，缝洞型油藏是目前发现的主要类型，定量表征缝洞型输导体系，能够提高对该类型油藏油气运聚成藏和富集规律的认识。缝洞型输导体系宏观尺度的地震表征可以描述其轮廓，无法精细刻画其强非均质性；镜下等微观尺度研究能够认识岩石学特征及成岩过程，但对其输导性的规律性表征较弱；而中观尺度研究能够利用岩心、测井和动态资料，认识输导体系的有效物性、确定其连通性、定量表征其输导性能。本项目以宏观和微观研究成果为约束，主要利用测井资料结合岩矿测试，分析洞穴充填程度和不同充填物的有效孔渗性能，认识缝洞输导体的中观尺度上有效物性；在此基础上结合生产动态等资料，分析输导体流体连通性；进而选择合适的参数组合，建立缝洞输导体输导性能定量表征与评价的方法；最后结合油田实际生产数据，对研究成果和认识进行检验。

输导体作为含油气系统的重要组成元素，是烃类从烃源岩运移到圈闭的路径。塔里木盆地塔中隆起碳酸盐岩断裂-缝洞输导体埋深超过5500米，其规模、几何形态和空间分布极不规则，输导性能具有强非均质性，导致含油气系统分析存在很大困难、增加了深层油气勘探的不确定性。因此，需要针对断裂-缝洞输导体系进行定量表征。.面对深层断裂-缝洞输导体非均质性强、多期油气混源成藏的难题，本研究采用数据驱动技术，有效综合了地质、地球物理和生产数据，建立了一种地质-地球物理综合表征方法，从微观-宏观-巨观尺度上对断裂-缝洞输导体进行了定量表征。（1）微观尺度（0.01~0.1 m）：以深层孔隙系统为切入点，通过详细的岩心和薄片观察，考虑沉积、成岩和构造等地质作用的联合改造，划分出18种岩石相；（2）中观尺度（0.1~10 m）：根据测井资料的纵横向分辨率和识别能力，对岩石相进行合并和拆分，划分出8种测井相和6种输导体类型，明确了缝洞输导体在井筒的发育情况与物性特征；（3）宏观尺度（10~1000 m）：以岩石相、测井相、输导体类型为约束，采用数据挖掘的方法，划分了缝洞输导体的5类地震相，明确了缝洞输导体在井间的发育特征与分布规律；结合走滑断裂的三维解释，建立了断裂体系与岩溶体系所构成的三维输导格架。（4）流体性质分析：根据井筒测试结论、测井解释油气水层结果，结合单井产能数据，反推断裂-缝洞输导体系的多期油气成藏过程，明确了三期油气成藏对现今流体分布的影响。.本研究融合了断裂-缝洞输导体系的地质理解、地球物理响应和数据挖掘技术，实现了微观-宏观-巨观尺度之间的无缝连接，成功应用于塔里木盆地塔中隆起碳酸盐岩断裂-缝洞输导体建模与含油气系统分析。该工作流程也可以应用到相似的古岩溶油气藏和碎屑岩油气藏的输导体系的研究。