Analysis on exploration potential of mid-low rank coalbed methane in Shenfu Area of Ordos Basin

In order to analyze the exploration potential of mid-low rank coalbed methane in Shenmu-Fugu Area at east edge of Ordos Basin,though coal and rock proxi mate analysis,maceral, Ro,max,heat simulation and other experimental data statistics and contrastive,it was found that the hydrocarbon generation capacity of No. 8 + 9 se am was higher than No. 4 + 5 seam. The result of desorption experiments showed that,the coalbed methane content of upraised area at east part of study area was low an d was adsorption gas mainly due to the seam and underground water conditions were not suitable to biogas generation and the exploration potential was insufficient. The s trata in west of the area were in gentle slope area. Especially in anticline development area,due to the pore permeability of medium and mid-low rank coal relatively develo ped,free gas content could be increased and could be over the adsorption gas. Based on high rank coal reservoir →low rank coal reservoir→normal gas formation reserv oir,and the gas-bearing variation law was adsorbed gas→adsorbed gas and free gas一+ free gas,in combination with other coalbed methane deposition conditions,the " str ucture highs" or trap would be favorable direction to coalbed methane exploration in the area.