Geologic Condition And Resource Potential Of CBM In Gemudi Syncline

The research on the geological characteristics and recoverability of coalbed methane is an important basic work for the exploration and development of coalbed methane,which has great development significance.This dissertation takes the Gemudi syncline in western Guizhou as the research object which had multiple coal seams,and analyzes the gas bearing characteristics of the main coal seams based on the characteristics of coalbed methane reservoirs,structural features and mining geological conditions,etc,and also predicts the amount of geological resources of coalbed methane by experimental methods.This dissertation uses the isotherm adsorption to calculate the coalbed methane recovery rate combined with the status of exploration and development in the research area,and evaluates the potential of coalbed methane resources in the study area based on the amount of resources and recovery.Forecasting the amount of deep coalbed methane resources in the nuclear section of the syncline y drilling data of the shallow part of the syncline.The results show that the abundance of coalbed methane resources of the main coal seam in the study area is 499million m~3/km~2,the shallow geological resources with a depth of 1000m account for40.09%,showing good resource potential and coalbed methane mining conditions.The calculation of coalbed methane recovery rate by isothermal adsorption method shows that the recovery factor is equivalent to the well-developed part such as southern Qinshui Basin and Fuxin Basin,which has a good prospect of coalbed methane development.And the shallow coalbed methane can be mined at 1000m is 18.172 billion m~3,the abundance of recoverable resources is 312 million m~3/km~2.On the basis of the amount of resources,evaluated the potential of coalbend methane resources by divided the study area to four parts.The results show that the Miluo-Aga block has the greatest potential,followed by the Yushe-Ega block,and the Sutian-Machang block and the Yanjing block are inferior to the former two.