According to the geological theory of "source-control" (i.e.

hydrocarbon accumulations are under the control of source rocks)

we made geostatistics on distributions of source rocks and reservoirs in China's eastern basins.Based on these statistical data

we brought forward a concept of "hydrocarbon distribution threshold"

which lays the foundation for concepts such as "probability of hydrocarbon pooling"

"probability of reserve distribution" and "maximum size of reservoir".A multivariate nonlinear mathematical model was established by using the geostatistics and regression discrimination approaches.We made a comprehensive prediction on the hydrocarbon distribution in the Bozhong depression of the Bohai Sea waters according to the hydrocarbon expulsion threshold

hydrocarbon pooling threshold and hydrocarbon distribution threshold.The results show that

the favorable plays are the Shijiutuo pooling system and the Bodong pooling system.Favorable exploration targets will be traps which are adjacent to the boundary of hydrocarbon expulsion and have an over 80% probability of hydrocarbon pooling.