Abstract: From the vertical and horizontal difference, study on post-salt reservoir formation features and distribution rules in southeastern Pre-Caspian Basin is studied. It points out that oil and gas migration in post-salt strata has five distinctive features as follows: ① Valid salt window formed by salt movement is the main migration pathway of post-salt reservoir; ② The critical stages of post-salt reservoir formation are P-T, T3-J, J2-K, and the end of T3 is the most important stage; ③ The horizontal distribution of hydrocarbon is always zonal, with its overall trend of K1, J2 inspissated pool in salt dome core and T2 gas pool as well as hydrocarbon reservoir & T1, P2 oil reservoir in salt dome flank and Inter-Salt Dome; ④ Late preservation is the key factor in forming post-salt high-grade commercial reserves reservoir; ⑤ T anticline and faulted -anticline trap under stable J in Salt flank is the most favorable exploration target

Key words: Pre-Caspian Basin, post-salt strata, hydrocarbon migration and accumulation, reservoir formation model