木里地区天然气水合物储层参数计算

测井作为一种重要的地球物理勘探手段,在天然气水合物资源定量评价中发挥着重要的作用,随着木里地区天然气水合物勘探井的日益增多,需建立一套适合本地区的泥质含量、含水饱和度和孔隙度等储层参数的计算方法,这对储层优选、资源量的评估等具有重要意义.笔者基于国内外文献常用的天然气水合物测井评价模型,选用经过环境校正和标准化处理后的测井数据,定量计算天然气水合物的孔隙度与饱和度等参数,结合岩心测试和岩电资料,修正并完善储层参数的计算模型,分析各种测井评价方法在水合物储层计算当中的优劣.研究结果表明:泥质含量选用自然伽马值求取为宜;孔隙度选用受水合物分解所产生气体影响较小的密度值求取;饱和度的求取需根据水合物含量的不同,分别选用印度尼西亚公式、修正的wood方程或修正的阿尔奇公式.

Parameters calculation for the gas hydrate reservoir in Muli area

As an important geophysical exploration means,the well-logging plays an important role in quantitative evaluation/assess ment of natural hydrate.With more and more natural gas hydrate being explored in Muli area,a calculation fit for the local shale content,water saturation,porosity and other reservoir parameters is necessary,which is significant for the reservoir optimization and source assessment.Based on the evaluation model of gas hydrate frequently used in the literatures both in China and abroad,the authors consulted the well-logging data of Muli area processed through environment adjustment and standardization,and calculated quantitatively the porosity,saturation and other parameters.With core testing and core electricity data,the authors also amended and improved the parameters calculation models,and analyzed the advantages and disadvantages of different well-logging interpretations applied in gas hydrate reservoir calculation.The results show that the shale content was obtained through natural gamma,the porosity was obtained through gas density resolved by hydrate and had less impact,and saturation was obtained by Indonesia's formula,amended equation and Archie's formulas according to different hydrate values.