Study On The Fluid Seismic Distinguish Technology In Shallow-fluvial Facies Reservoir Of Jiyang Depression

The oil-gas reservoirs of shallow fluvial facies is rich in Jiyang Despression.but because of different sedimentary microfacies,reservoir thickness,fluid type,saturation and etc,this kind of reservoir have variety of complex seismic reflection characteristics: some times bright spot and some times dim spot.So it's difficult to predict reservoir and fluid.The paper made the study of shallow fluvial facies reservoir in Jiyang exploration area as the main research object.On the basis of rock physics analysis,using the forward modeling technology,carried out the shallow fluid identification and seismic prediction.The research shows that difference of fluid type have different influence on the shallow sandstone reservoir of its velocity and density,the difference of physical property of gas reservoir mainly accounts for its velocity and density decrease,For the oil,the change of reservoir velocity and density not only with its properties,but also related to early filling of oil and gas.Reservoir thickness and physical properties make greater contribution on seismic reflection than the oil in the reservoirs,the influence on the variation of post-stack amplitude and frequency is mainly caused by the thickness and structure changes of the reservoir.Spectrum attenuation is associated with reservoir fluid,different reservoir fluid properties,different attenuation degree.The elastic parameters of the prestack elastic inversion technique,such as poisson ratio and ect,which used to identify the reservoir fluid,made good effect.