利用干井测井曲线确定煤层厚度方法研究

Study on method of determining coal seam thickness with dry well logging curve

煤田地球物理测井是煤田勘探中确定煤层厚度的主要依据,但在一些地区因钻孔漏浆严重,无法测量三侧向电阻率和声速曲线,煤岩层的识别和定厚只能采用放射性测井曲线。通过分析研究区密度、自然伽马和伽马-伽马等测井曲线的形态及组合特征,对井田的煤岩层进行综合对比。提出标志层与测井曲线相结合的煤岩层识别与定厚方法,在研究区确定了曲线特征相对稳定的两个标志层,有效解决了煤岩层识别和定厚问题。

Coalfield geophysical logging is the main basis to determine the thickness of coal seam in coal exploration,but in some areas,for the serious drilling slurry leakage,there is no way to measure the three-lateral resistivity and the sound velocity curve,so it is only the radioac-tive logging curve that can be adopted for coal seam identification and thicknessing. Through the analysis on the study area density,the shapes and the combination features of the natural gamma and gamma-gamma logging curve,etc.,comprehensive comparison on coal seam is completed in the mine field. The method of combining marker bed and logging curve for identification and thicknessing of coal seam is proposed,and two marker beds with relatively stable logging charac-teristics are determined in the study area,which have effectively resolved the problems of identi-fication and thicknessing of the coal seam.