摘要
自然伽马测井主要受地层中自然伽马射线强度的影响,但围岩的吸收系数也会对自然伽马测井曲线产生影响。运用数值积分的方法推导了在伽马光子能量恒定但吸收系数不同情况下有限厚放射性地层伽马射线沿井轴的分布,并据此开展了数值计算。得出了不同层厚条件下,围岩的吸收系数不同于地层吸收系数的情况以及厚度相同、围岩的吸收系数不同对应的理论曲线。直观地表示了它们对地球物理测井的影响,为进一步研究提供了有用的基础资料.
The Gamma—ray logging is measurements of natural Gamma—ray intensity in borehole, but absorption coefficient of the surrounding rocks is also important for the Gamma—ray logging.We use the method of numerical integration to derive the formula of Gamma—ray distribution on the axis of well.It is assumed that the power of the Gamma—ray is constant and the absorption coefficient is variable.Results are calculated numerically for different thickness and different value of absorbing coefficient.The work is helpful for further investigation.
出处
《吉林大学学报（地球科学版）》
EI
CAS
CSCD
北大核心
2006年第S2期166-168,共3页
Journal of Jilin University：Earth Science Edition
关键词
围岩
自然伽马测井
数值积分
吸收系数
surrounding rocks
Gamma—ray logging
numerical integration
absorption coefficient
