祁连山冻土区天然气水合物层位测井物性分析

摘要

This paper aims at obtaining a calculation equation for the formation porosity and natural gas hydrate content applied to Qilian Mountain permafrost area.Based on the laboratory test data of two cores,the authors adopted the multiple linear regression to get the porosity calculation equation applicably.And by referring to the relevant data obtained both in China and abroad,the mofified Archie Equation was employed to calculate the hydrate concentration and to get the concentration values of five hydrate formations with log da-ta.A comparison with the value obtained from the univariate equation shows that the value from the ternary linear regression porosity e-quation can achieve better accuracy (up to 85%)with the test data of the core.The value range of the hydrate concentration is between 11.47% and 81.61%.The results obtained by the authors can provide valuable reference for the evaluation of the natural gas and hy-drate in this area.%笔者旨在总结出一套适用于祁连山冻土区地层孔隙度和天然气水合物含量的计算方法。利用2个钻孔的岩芯实验室测试数据，采用多元线性回归方法，得到了适合本地区的孔隙度计算公式。通过参考国内外相关资料，采用修正的阿尔奇公式计算水合物含量，并求得了有测井数据的5个钻孔水合物异常层位的含量值。研究结果表明，三元回归的孔隙度公式比单变量回归的效果好，计算值与岩芯测试数据回归精度达到85％；计算的水合物含量值范围为11．47％～81．61％。本次研究成果对未来该地区的天然气水合物测井评价具有一定的参考价值。