S-shaped strike-slip transfer zone is widely developed structure in strike-slip strain background.However

previous researches are mainly focused on the classification of strike-slip transfer zones

but its control on hydrocarbon accumulation is poorly understood.Based on 3D seismic data and oil and gas fields analysis

this paper addresses the effects of S-shaped strike-slip transfer zone on hydrocarbon accumulation in the Liaoxi structural belt

Bohai Sea

by using statistical methods.Cenozoic structural deformation of the Liaoxi structural belt is characterized by deformation of NE-trending extension superimposed by NEE-trending dextral strike-slip activities.S-shaped strike-slip transfer zone can be divided into restraining bends and releasing bends.According to different evolution stages

restraining bends can be further divided into 3 subordinate classes

involving transpressional uplifting bend

gentle restraining bend and intense restraining bend.Similarly

releasing bends involve spindle-shaped pull-apart

lazy s-shaped pull-apart and rhomboidal pull-apart.In addition

the strike-slip transfer zones at the end of strike-slip fault zones contain restraining and releasing horsetails.The concept of oil and gas enrichment index (OGEI) is defined

and the positive correlation between master strike-slip fault curvature and intensity of adjusting strike-slip faults is proven.A mathematical model from OGEI is proposed to quantitatively predict oil and gas enrichment.It is a quantitative tool for exploration decision

and has been applied in analysis of LD5-2N oil field successfully.