塔河油田缝洞型储层中洞穴充填程度半定量化分析

洞穴是塔河油田十区奥陶系缝洞型碳酸盐岩储层的主要类型,钻遇洞穴型储层井往往高产稳产,而对洞穴充填程度的识别,是判断洞穴型储层有效性的关键。将洞穴充填程度分为充填、半充填和未充填三种类型,利用钻录井、常规测井、电成像测井以及交会图法判别洞穴型储层充填程度。利用Th对洞穴充填反应敏感特征,建立K(钾)和Th(钍)交会图,分析不同充填类型在交会图上的值域范围,得到了不同充填程度测井响应特征判别标准,用以识别洞穴型储层充填程度。经实例井研究表明,K-Th交会图能有效反映洞穴型储层充填程度。

Half quantitative analysis of filling degree in caved type reservoir of fractured-vuggy reservoirs in Tahe oilfield

The caved type reservoir was a main reservoir space type of Ordovician fractured-vuggy carbonate rocks in Tahe-10 area,well production in the case of this type was very high,therefore,the identification of its filling degree was the key to determine the effectiveness of the caved type reservoir.The filling degree could be divided into three types:complete filling,half filling and no filling.By using drilling and logging,conventional logging and electric imaging logging,the intersection graph method was used to determine the reservoir filling degree.According to sensitivity characteristics of Th(radioactive thorium)to the cave filling reaction,the intersection graph between K(potassium)and Th was established,the value range of the intersection graph under different filling degrees was analyzed,and then the well logging response characteristics under different filling degrees were obtained.Through concrete well examples,the application results indicated the intersection graph between K and Th can effectively reflect the filling degree of caved type reservoir.