The source rocks of discovered Carboniferous gas region both in central andeast Sichuan are underlying Silurian System.Though the thickness and organic abundance of the source rocks in central Sichuan are not as good as that inthe east part
the Ordovician System in central Sichuan is also fine source rock
which may make up a defect for Silurian.The porous bed of the Fucheng-zhai member in central Sichuan—the main reservoir—could be compared withthat of east Sichuan whether in the total thickness or the thickness percentage of the whole member and the weighted mean porosity.The southern part ofcentral Sichuan is in the upper part of a uplift
conditions for hydrocarbon migration and accumulation are no less favourable than that of east Sichuan.In especial
cap and trap conditions are evidently superior to that of the east.In consideration of the above conditions
the author proposed not to domore drilling in the north part
and that the south part should be an impor-tant target for hydrocarbon exploration in central Sichuan.