Elastic Impendence Inversion Based On Angle Stack

With the deepening of seismic exploration and increasingly complex geological conditions complexity, seismic inversion occupies a more and more important position in seismic exploration. Seismic inversion is understanding of underground lithology and the nature of the fluid contained by seismic data, estimating the impedance of the underground rock and other reservoir parameters, and preparing for exploration and development of underground resources. The traditional pre-stack seismic inversion can only get impedance information, it is limited in solving practical geological problems, is difficult to meet the needs of detailed description of reservoir in the development phase. The technology of pre-stack seismic inversion is a new technology to meet the increasingly complex ground conditions in the field of seismic exploration, that has become an indispensable method of forecasting oil and gas in some countries and the hot spots in inversion and seismic attribute analysis.Pre-stack seismic data contains richer underground geology, lithology, and oil and gas information than post-stack seismic data. The pre-stack inversion contains shear wave information. Not only can it predict sandstone, but also can separate the favorable reservoir from the sandstone. When the P-wave impedance can not reflect the lithology and favorable reservoir or when the seismic oil and gas bearing has a weak reflection, the use of pre-stack inversion has great advantage.With the deepening of oil and gas exploration, problems in the exploration and development of lithologic reservoirs and subtle reservoir attracted explorer's attention increasingly, more and more problems in the complex reservoir exploration and development, the problem that is urgent to be solved is improving reservoir prediction and description accuracy, solving the problem the spatial distribution of the reservoir, and designating the spatial extent of oil and gas reservoirs further. The pre-stack seismic inversion technology can make full use of abundant information of amplitude and frequency of seismic channel in the small, medium and large and the different angles and inverse vertical, shear wave impedance parameters, and shear and longitudinal wave velocity ratio, Poisson's ratio, Lambda-Rho and Mu-Rho, and other important elastic parameters at the same time. Determining the physical properties of reservoir and hydrocarbon potential has higher sound accuracy pre-stack elastic impedance inversion data, fidelity and reliability than the post-stack inversion. It is of great significance for reservoir prediction and reservoir characterizationAngle stacking technique as a AVO technology to find oil and gas layer directly is another special pre-stack data processing technique that is generated from today's big trend of seismic data processing and the development requirements of seismic data processing and interpretation toward the high accuracy, high signal to noise ratio and fidelity of the "three high" direction. Therefore, the angle stack is another new emerging technology in seismic data processing. This article achieved the desired results in angle stacking .Also proved that angle stacking can provide more reliable actual data for other AVO technology, AVO attribute analysis has higher accuracy on the basis of angle stacking data achieve better results in the AVO technique. At the same time we must do forward modeling strictly in the actual data processing and interpretation, so as to ensure the authenticity and reliability of overlay angle's effect, to ensure accuracy of the information further, thereby reduce exploration risk.The main content of this paper is to distinguish and identify oil and gas through the Shear wave velocity ratio, shear wave impedance, Poisson's ratio, Lambda-Rho and Mu-Rho, and other important elastic parameters acquired by the inversion overlay data of different angles. Finally citing the application example make the elastic impedance (EI) inversion on angle gather information of different perspectives in a work area, Extracted the shear wave velocity ratio, Poisson's ratio, Lambda-Rho and Mu-Rho and other elastic parameters, do intersection and identify oil and gas by the elastic parameters obtained, which achieved good results. Confirmed that the method has the advantage in complex reservoir description and fluid identification. It showed that the method is practical.