陕北盐池区块复杂油水关系储集层录井识别方法

Identification method of mud logging for complex oil-water relationship reservoir in Yanchi block of northern Shaanxi

陕北盐池区块位于鄂尔多斯盆地西北部,区内天然裂缝发育,油气水关系比较复杂,整体勘探程度较低。在详细阐述利用特色录井技术(岩石热解、热解气相色谱、轻烃录井)识别盐池区块储集层复杂油水关系的基础上,建立了适用于盐池区块流体性质识别的解释标准与评价方法,利用岩石热解地化录井技术定量化识别储集层的含油性,并结合轻烃、热解气相色谱对盐池区块储集层的原油组成成分进一步识别,实现了这些评价方法之间的优势互补,从而弥补了仅利用单项录井技术解释评价油气层的不足,提高了储集层解释评价的准确性,综合解释符合率由73.23%提高到81.25%,在盐池区块复杂油水关系储集层勘探开发中见到了明显的效果。

Yanchi block in northern Shaanxi is located in the northwest of Ordos Basin,where natural fractures are developed and the oil-gas-water relationship is relatively complex,so the overall exploration degree is low.In this paper,the application of characteristic mud logging technology(rock pyrolysis,pyrolysis gas chromatography,light hydrocarbon logging)is described in detail.Based on the identification of complex oil-water relationship of reservoir in Yanchi block,the interpretation standard and evaluation method suitable for fluid property identification in Yanchi block are established.The oil-bearing property of reservoir can be quantitatively identified by using rock pyrolysis geochemical logging technology,and the composition of crude oil in the reservoir of Yanchi block is further identified by combining with light hydrocarbon and pyrolysis gas chromatography.The advantages of these evaluation methods are complementary,so as to make up for the deficiency of using single mud logging technology to interpret and evaluate oil and gas reservoirs.The accuracy of reservoir interpretation and evaluation is improved,and the coincidence rate of comprehensive interpretation is increased from 73.23%to 81.25%,which shows obvious effects in the exploration and development of reservoirs with complex oil-water relationship in Yanchi block.