With the increasing of exploration maturity

the focus of exploration target evaluation has gradually shifted from basins to plays and traps.As the major targets to hydrocarbon discovery

preliminary exploratory plays are the main targets to achieve exploration benefit.However

evaluation of preliminary exploration target is very challenging due to the low exploration maturity and multiple evaluation parameters which are difficult to quantify.Based on the principles of exploration risk analysis

this paper established the model of probability of hydrocarbon discovery-strategic value of resources for evaluation of preliminary exploratory plays

and provided relevant assessment parameters

assignment criteria

computational formula and results classification methods

making it possible to evaluate preliminary exploration target on an unified platform.Five preliminary exploration plays in the Sichuan Basin

such as Tongnanba

Exi-Yudong

Nanjiang

lower combination of southeast Sichuan and Zhixinchang-Longbaoliang

are selected and evaluated with this model.