| With the breakthrough in understanding and exploration techniques, a series of important discoveries were made in petroleum exploration of carbonate rocks in the world, the climax of finding oil and gas in carbonate rocks war set off. Carbonate reservoirs play an extremely important pole in oil and gas production of the world. According to statistics, the world's oil and gas production in carbonate reservoirs is accounted for about 60% of world oil and gas production. Among them, the world's reef reservoir is accounted for about 12% of oil and gas proved reserves. Therefore, the study of carbonate reservoir characteristics, distribution of oil and gas and petroleum geology and reservoir combinations characterization has important theoretical value and practical value.With the global increasing demands for oil and natural gas, simple seismic exploration methods have been unable to meet the exploration requirements of oil and gas reservoir which is buried in deeper and more complex structure. It's considered to use as more as possible amount of information from the seismic data. To a large extent, a lot of useful information is submerged in post-stack data. Through the analysis of pre-stack data, we hope we can find more useful information, for example, pre-stack seismic data contain more information of the reservoir fluid. In recent years, based on pressure wave and shear wave, scholars conducted extensive research in identification of reservoir fluid. Through research, It's showed that shear wave is stronger than pressure wave at the side of the expression of fluid information. However, due to the high cost, difficult technology and so on, S-wave exploration has not been well implemented and widely used. Study also showed that when incidence is vertical, only P-wave reflection occur, rather than the converted S-wave occurs at the interface with normal incidence. When Non-vertical incidence, S-wave occurs at the interface. To this end, the utilization of pressure wave, shear wave and the converted shear wave provides an effective way and direction for the identification of fluid. Thus, AVO related technology which is to study the amplitude versus offset has been deeply researched. AVO technology is based on rock physics and rigorous mathematical derivation, at the same time, the data processing procedure has a certain noise immunity, and S-wave information can be extracted from the P-wave. Therefore, this technology has been the rapid developed and wide applied, and become an important way for oil and gas exploration and reservoir prediction.By learning and understanding the AVO technology background, history, current research situation and development trends, this article introduced the basic principles of AVO technology and its rock physics basis, introduced Zoeppritz equation and its approximate expression in different ways, and discussed the accuracy of different approximate expressions. Then, the paper showed the research results of the characteristics of the seismic response of reef reservoir which is the focus of this paper. At the same time, the definition and classification of reef has been studied. Combining with the characteristics of seismic response of reef flat in the actual data, I have a more profound understanding. In the analysis of theoretical model, first of all, it is analyzed that a variety of rock physical parameter's the corresponding impact to the theoretical model. Based on the carbonate reef flat model, we do AVO forward modeling and inversion of conventional properties. Based on theoretical analysis, we researched AVO attribute of the actual data in an area which is in southwestern China. We do cross-plot analysis of some of properties which is good and find a potential anomaly of gas reservoir in the region。...
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