Relationship between natural decline rate and composite decline rate.;

In view of the predicting circumstance by experience in the past,formula of monthly natural decline rate is deduced in the regular pattern of exponential decline,double curves decline and harmonic decline.

Affecting factor analysis and countermeasures on the natural decline in Extra-complicated Fault Block oilfield;

Study of natural decline models based on three phase percolation mechanism-taking Wenmi oilfield as example.;

Factor analysis and countermeasures on the natural decline in Qiaokou oilfield.;

By means of total differential analysis method, it is pointed out the formerly proposed method of modifying Cobb-Douglas production function by adding natural productivity decreasing rate and cost increasing rate has an unrealistic supposition, that is, it implies that resource stock of oilfield impacts output through weakening of technology progress.

Meanwhile,the author divides the oilfield production decline rate into the liquid production rate natural decline and t.

A differential equation for production decline rate is set up based on the study of variation of production decline curve,by which the dimensionless decline equation for describing the production decline rule is deduced.

In order to increase prediction accuracy of development blocks with short production history,this paper introduces multiple regression method through three following aspects: prediction of decline index and initial decline rate;prediction of annual decline rate;prediction of injection-production ratio.