Application of AVO Fluid Inversion Technology in Yong’an Area of Subei Basin

AVO fluid inversion technology can quantitatively determine the probability distribution of fluids in reservoir and decrease the uncertainty of AVO analysis. The forward model with many types of fluid combination can be synthesized from logging data by using of Monte-Carlo method, the templet of oil, gas and water distribution can be gotten, which can be calibrated with the models and production data, thus whether the templet is right or not, which can be verified. The gradient and intercept of the 3D seismic data can be computed by the Shuey’s function; compared with the templet, the probability of hydrocarbon fluid can be estimated by means of the Bayes theory. The fluids in reservoir and the burial depth of the reservoir are the main factors that affect the results of AVO fluid inversion. AVO fluid inversion technology is applied to estimate hydrocarbon probability in the target layer in Yong’an area of Subei basin. Combining with drilling data, the results shown that this technology could reduce the uncertainty of estimation and increase the drilling success rate.