Abstract: The wethod proposed in this paper is a new method which identifies g as bearing zones by using an equivalent difference ratio of elastic modulus (EDR) of formation rock. The ratio is calculated by the conbination of sonic log, density log and neutron lob. The formula used to calculate the ratio is as follows.EDR=E_CW-E_C/E_C in which, E_C is the equivalent elastic mode lus of the interested formation rock dyne/cm²; E_CW is the equivalent elastic modules of the 100 fo water saturated rock of the 100% terested formation, dyne/cm².

摘要： 识别气层的普通方法是以中子测井孔隙度与密度测井孔隙度比较为基础。在低孔隙度、变化的骨架地层中,识别气层常常是困难的。本文提出的测井识别气层新方法,首先是用声波测井、密度测井和中子测井信息计算岩石等效弹性模量差比值(EDR)、,然后用它评价天然气层。计算岩石等效弹性模壕差比泣的公式如下:EDR=E_CW-E_C/E_C式中EDR-岩石等效弹性模量差比值,无量纲;EDR——岩石等效弹性模量,达因/cm²;E_CW—完全含水岩石等效弹性模量,达因/cm².在一般情况下,当岩石等效弹性模量小于完全含水岩石等效弹性模敛时,岩石等效弹性模量差比值大于零,指示是气层,反之,当岩石等效弹性模量等于完全含水岩石等效弹性模量时,岩石等效弹性模量差比值等于零,指示是非气层。、该方法用于评价砂岩气层与碳酸盐岩气层,提高了测井直观识别气层的分辨率于解释精度。