Establishment of classification and evaluation standard of coalbed methane in GZ area by well logging cross plot technology

The prospect of coalbed methane resources is an important guidance for the determination of exploration targets. By collecting the data of mud logging, well logging, coal core, analytical test and drainage in GZ area, using the technology of coal core calibration logging and mathematical statistics, the quantitative interpretation model of coalbed methane(CBM) evaluation parameters(ash, volatile matter, fixed carbon, moisture) and the evaluation model of coalbed methane content are established. On the basis of comprehensive analysis, the method of establishing intersection charts by using single-layer gas production measurement and well-logging calculation of ash content, fixed carbon, gas content and combined production thickness is used to form the evaluation criteria for CBM reservoir classification, and then the division and evaluation of favorable CBM reservoir sections are realized.