Abstract: In view of the petroleum geologic conditions and exploration degree of Ordovician in Tahe oilfield, three different methods such as pool size sequence, resources area abundance and geologic factor regression are selected for prediction/estimation of its potential resources. The study shows that the results given by these three methods are quite consistent and have good comparability. The predicted petroleum resources in place of Ordovician in Tahe oilfield amount to about 1.414×10⁹ t, which provide the geological basis for oil-gas exploration planning and preparing the mid-and long-term development goals in this area.

Key words: Tahe oilfield, petroleum resources, pool size sequence method, resources area abundance method, geologic factor regression method