海陆过渡相不同源储类型页岩储层关键参数测井识别及分类方法

Logging interpretation and classification method of reservoir parameters of marine continental transitional shale based on source and reservoir type

为完善海陆过渡相页岩储层分类方法,以鄂尔多斯盆地东缘临兴区块为例,在划分页岩源储类型基础上,结合电阻率、声波时差、补偿中子、自然伽马等常规测井和成像测井,利用页岩样品实验结果校正,优化了不同源储类型页岩的岩性、有机碳、孔隙度、含气量等关键参数测井解释模型,建立了海陆过渡相页岩气储层分类方法。结果表明:①海陆过渡相泥页岩存在砂质夹层型、灰质混积型和富有机质泥岩层理型三大类源储类型,利用声波、密度与自然伽马的3D交会图与成像测井可识别各类型岩性;②不同类型泥页岩的测井解释优化模型拟合结果显示区内页岩储层参数相对有利勘探,其中砂质夹层型页岩有机碳含量为0.25%~6.66%,孔隙度为0.10%~4.92%,含气量为0.15~4.39 m^(3)/t,平均脆性指数为45%;灰质混积型泥页岩有机碳含量为1.98%~8.66%,孔隙度为0.31%~4.01%,含气量为0.82~3.72 m^(3)/t,平均脆性指数为43%;富有机质层理型页岩有机碳含量在2.04%~14.53%之间,孔隙度为0.29%~5.29%,含气量为0.93~5.14 m^(3)/t,平均脆性指数为37.54%;③建立的以源储类型为核心的“三型九类”页岩储层分类方法具有实用性,其中I类、II类夹层型页岩和I类富有机质层理型页岩已在生产实践显现开发潜力。

In order to divide shale reservoir of marine-continental transitional facies,taking Linxing block on the eastern edge of Ordos Basin as an example,the logging interpretation methods of key parameters and the classification method were established,based on the classification of shale source reservoir types,combined with conventional logging and imaging logging,used the correction of shale sample experimental results.The results showed that:(1)Three types of source reservoir types were divided,which named sandstone interlayer type,lime mixed accumulation type and organic mudstone bedding type.Various types of lithology can be identified by using 3D cross plot and imaging logging of acoustic wave,density and natural gamma ray.(2)Logging interpretation of reservoir parameters is favorable for shale exploration in the work area.The organic carbon of sandstone intercalated shale was 0.25%-6.66%,the porosity was 0.10%-4.92%,the gas content was 0.15-4.39m^(3)/t,and the average brittleness index was 45%.The organic carbon of lime mixed shale was 1.98%-8.66%,the porosity was 0.31%-4.01%,the gas content was 0.82-3.72 m^(3)/t,and the average brittleness index was 43%;organic carbon of organic rich bedding shale was 2.04%-14.53%,porosity was 0.29%-5.29%,gas content was0.93-5.14 m^(3)/t,and average brittleness index was 37.54%.(3)The“three types and nine types”shale reservoir classification method with source reservoir type as the core was established and it was practical,which showed class I and class II sandwich shale and class I organic bedding rich shale had development potential in production practice.