塔河油田碳酸盐岩储层测井多井评价研究

Log and multiwell evaluation of carbonate reservoir in the Tahe oilfield

1. 中国石油大学地球资源与信息学院,山东东营 257062;2. 中国石化石油勘探开发研究院南京石油物探研究所,江苏南京 210014;3. 大港油田博士后流动站,天津 300280

Institute of Geophysical Prospecting, SIN OPEC Research Institute of Petroleum Exploration and Development, Nanjing 210014, China

常规测井资料主要用于识别大段低孔隙地层中明显的缝-洞型储层特征,对于裂缝性和孔隙性储层,由于受测井资料分辨率的限制,识别较为困难,而微裂缝和溶蚀微孔储集层则几乎无法识别。为了使常规测井资料能有效反映碳酸盐岩储集层孔、洞、缝的特征及其变化,突出不同缝、洞层的响应特征,并划分出不同类型的储层,对测井资料响应特征敏感性进行了分析。以新疆塔里木盆地塔河油田碳酸盐岩储集层基本特征为依据,利用常规测井信息比值法和重叠法等技术,分类提取了储层测井特征参数:①岩电测井特征参数(包括井径比K₁、深浅电阻率比K₂、自然电位相对比K₃);②孔隙测井特征参数(包括声波时差比K₄、密度比K₅、中子相对孔隙度K₆);③能谱测井特征参数(包括铀相对含量K₇、钍铀比K₈等),并进行了综合评判,确定出划分储层类别的标准。经过50口井的应用验证,采用多参数综合评判来划分地层和储层是可行的,效果也很明显。

Conventional log data is mostly used in identifying low-porosity formation where fracture and hole both are great in a larger segment. Because of the lower resolving a bility of conventional log, it is difficult to identify fracture formation or low-porosity zone naturally. For micro-fracture and corroded micro-pore reservoir, conventional log is impossibility to identify them directly. In order to use conventional log to identify efficiently reservoir types with different pore, cave and fracture features, we must study conventional log response of pore, fracture and cave and enlarge them.The primary work is to study the log sensitivity to different reserve space. According to the carbonate reservoir’s character of Tahe oilfield in Tarim basin. Xinjiang, using conventional log data ratio-computing and o verlapping technologies, this paper pick up reservoir’s classification character parameters:Crock resistivity parameters, ratio of caliper Kl, ratio of deep to shallow resistivity K2,ratio of relative spontaneous K3;Porosity parameters, ratio of acoustic wave time difference K4,ratio of density K5,neutron relative porosity K6;Energy spectrum parameters, relative content of uranium K7, ratio of thorium to uranium K8. Then synthesis estimation is carried out and the criterion of determining reservoir types is established used them in formation distinguishing and reservoir identifying.This work broadened the applying area of conventional log data.The effect is very evident.