Abstract: Recently, a major breakthrough has been achieved in lithologic reservoirs in the eastern slope of Fukang Sag—Well
Kangtan 1, a risk exploration well of PetroChina, which obtained high yield oil flow of more than 100 tons from each of the two
layers in the Permian. The favorable conditions for hydrocarbon accumulation have been systematically discussed based on understandings of Well Kangtan 1 to evaluate the exploration potential and prospects in Fukang Sag. Results show that there are two sets of large-scale source rocks in the Permian and Carboniferous in Fukang Sag, which provide promising hydrocarbon source
potential. Controlled by the paleo-geomorphology, two sets of thick and large-scale reservoirs in the Middle and Upper Permian
are developed in the eastern slope and sag area with similar distribution pattern, providing favorable conditions for the formation
of lithologic-stratigraphic oil and gas reservoirs. The well-matched time-space configuration of thermal evolution of source rock
and tectonic evolution, and the late sealing conditions in the updip direction result in the differential accumulation and orderly
distribution of two-stage oil and gas reservoirs. The sag area is the main field for late accumulation of oil and gas. The three
sub-sags in the slope are favorable exploration targets in Fukang Sag, which show great potential for large-scale exploration of
lithologic reservoir in slope and sag areas.