The Research And Application Of Wide And Narrow Azimuth 3D Survey

This paper introduces the history of total 3D survey, acquisition methods of wide and narrow azimuth observation and their advantages and disadvantages. And then, the differences are compared and analyzed form wide and narrow azimuth observation attributes. Based on infilling shots method, the designing principle, major parameters as well as its characters have been studied in detail. AVO theory, several different approximations of Zoeppritz equation in wide azimuth observation, the analyzing method and processing technique are discussed. AVO response is studied with model data. Anistropic NMO method of wide azimuth 3D seismic exploration is discussed. On the theory of velocity analysis, the conventional velocity analysis and its affection to NMO are analyzed.Through the wide azimuth survey example, the major parameters, affective factors and resolvent in observation system designing have been analyzed. The offset distribution of the wide azimuth observation is not better than that of the narrow azimuth observation. But it can bring us abundant geological information. It is very useful for the research of azimuth anisotropy, lithology reservoir and sediment phase. It is the most effective method adopted in the prospecting field of complex structure, stratum and lithology trap oil/gas reservoir. But the wide azimuth needs high folds– that means more equipment, money and personnel involved.The narrow azimuth is very simple. Its offset distribution is better than the wide azimuth and it costs little. All the attributes are good for field QC and in-door data processing. It will be your preference in the survey of slight azimuth anisotropy, simple structure and complex surface such as mountainous area.