The present work aims to analyse the influence of present-day burial depths of coal seams on the sorption properties towards CHsub.4 and COsub.2, respectively. For medium-rank coals located in the southwestern area of the Upper Silesian Coal Basin (USCB), the gravimetric sorption measurements were carried out with pure gases at a temperature of 30 °C. The variability of COsub.2/CHsub.4 exchange sorption and diffusivity ratios was determined. It was revealed that in coal seams located at a depth above 700 m, for which the sorption exchange ratio was the greatest, the process of COsub.2 injection for permanent storage was more beneficial. In the coal seams lying deeper than 700 m with a lower COsub.2/CHsub.4 sorption ratio, the CHsub.4 displacement induced by the injection of COsub.2 (COsub.2-ECBM recovery) became more favourable.