珑东地区长8高阻油水层成因分析与测井识别方法研究

Researches on Genetic Analysis and Method of Identification with Logging in High Resistivity Oil/Water Layers of Chang8 Reservoirs in Eastern Gansu Area

鄂尔多斯盆地陇东地区延长组长8主要发育中高电阻率油层，受早期成藏因素影响，出现油层与高阻水层伴生的局面。这类高阻水层试油一般出水较大，导致无效压裂试油。基于高阻油水层的岩石物理实验和测井响应分析了其成因，并针对其成因和高阻油水层与正常油层测井曲线特征差异，提出了阵列感应侵入分析法、微差分析法，并引入核磁扫描测井识别陇东地区长8储层流体性质，测井解释符合率达到97．2％，应用效果良好。

There were mainly mid-to-high resistivity oil reservoirs developed in the Yanchang Formation Chang8 strata of the Longdong （eastern Gansu） Area of Ordos Basin. Influenced by the factors of the early stage reservoir-forming, the oil reservoirs were associated with high resistivity water layers. Generally a large amount of water is produced from the tesliug for oil in the high resistivity water layers, and thus leading to an invalid fracturing lest for oil. The reason has been analyzed on the basis of petrophysieal experiments and log responses of the high resistivity oil/water layers. In view of the reason as well as the differences hetween characteristics of the logging curves of the high resistivity oil/water layers and the norreal oil reservoirs, the authors put forward the array induction and invasion analysis, and differential analysis methods. Nuclear magnetic scanning logging was inrodueed to identify the properties of the fluid in the Chang8 reservoirs of Longdong Region, The coincidence rate of the logging interpretation has reached 97.2 %. indicating a good effect of application.