AVO分析与地震资料叠前储层预测技术

In this paper we base on the anisotropic theory and Zoeppritz function of the transmission theory and the law of amplitude versus offset simplify seismic reflection coefficient of different media, analyze the characteristic of the gas or oil saturated stratum or the VTI and HTI models. Discuss the P wave reflection relationship and the meanings of the different parameters. We use measured parameters of a reservoir to simulate the characteristic of the reservoir, study the different effects of stratum saturated with gas or oil and analyze the characteristic of the seismic response of different models which change with different incident angles and different azimuths. Using the field data of logs ,analyze the rock property parameters, build the relationship of logs and parameters by Gassmann theory or empirical function. Calculate the density and the shear modulus and bulk modulus, reconstruct the log curves, calculate shear wave logs and correlate the logs affected by mud and other environmental factors. Finally perform the relationship of the seismic data log of saturated stratum and enhance the ability and reliability in reservoir prediction. Our aim is by the prestack seismic processing to get high solution and amplitude preserved seismic data. Because in incident angle gathers or azimuthal gathers, the low signal to noise ratio and low different covers affect the result of the prestack reservoir prediction. We apply prestack noise erase, cell regularization process and relatively amplitude preservation in the high solution seismic process routine to preserve the characteristic of stratum response, and erase the effects of the noise. In this paper we finished prestack invertion in the BYT survey and fractured reservoir depiction in MB survey. By the invertion and multiple attributes crossplot. we can get the stratum profiles and oil indicator profiles which can predict the distribution of the reservoir and oil. In the MB survey, we get orientation and density of fractured reservoir by the azimuthal seismic amplitude and depict the potential oil and gas reservoir. Prestak invertion works better in distinguishing oil and reservoir.