By the analysis and study of a special kind of overthrust fault occurred in the lower layer B 2 of B coal group in Furong Mine,a new method for quantitative prediction,the method of elevation difference value of relative bed interval,is presented.

Qingxi field is located in middle of overthrust nappe in northern margin(Kulongshan)of Qilianshan mountain where in-tensive piedmont fold is associated with a series of huge overthrust fault structures which are characterized by advanced and im-bricate overthrust faulting toward surface and related folds.

Based on the research of development characteristics of overthrust fault, its sealing mechanism is ana- lyzed.

The effects of overthrusts on gas migration and accumulation in the north belt of Kuche depression;

The formation and evolution of Yanshan, which is a intraplate orogenic belt, began in Late Triassic Epoch, and its fundamental tectonic framework is characterized by a large tectonic wedge trending north formed in the period from Early Jurassic Epoch to Early Cretaceous Epoch, which is a overthrust-nappe system.

Nitrogen injection being used to enhance oil recovery in many oilfields, particularly in overthrust fault.

Through the summary of sealing capacity, types of hydrocarbon spilling (orleaking) and differential entrapment model, the authors discussed the hydrocarbon migra-tion and entrapment model within faulted structure and top leaking differential entrapmentfor series of fault traps by taking Biyang depression as an example.