| Marine carbonate regions in south of China are important areas for oil and gas exploration. In recent years, with further oil and gas exploration work, the natural gas field with the largest reserves- Puguang large field was found that in the northeast of Sichuan. The main layer of Puguang field was Feixianguan group, and its favorable facies was the platform marginal shoal, which indicates that the Feixianguan group in the northeast of Sichuan has a good exploration prospects and Tongnanba tectonic belt belong to the northeast of Sichuan develops the Feixianguan Formation oolitic reservoir too. The study area of this paper–HCL exploration area is located in the eastern part of Tongnanba exploration area in Northeast of Sichuan, and oolitic reservoir develops in this area. But it is difficult to carry out more accurate predictions for this kind of reservoir by a single type of geophysical methods because that the oil and gas exploration level in HCL area is less and the study of sedimentary facies and reservoir is not in depth enough, but also carbonate reservoir itself has a strong heterogeneity.Carbonate oolitic beach of Si Chuan have some characters,such as wide rang,great difference between oolitic and surrounding rock,high heterogeneity, heterogentic distribution in horizontal and vertical direction,high burial depth。As a result of the geological characteristic multiplicity and complexity,the exploration difficulty is very big。In view of the ooitic reservoir's geological characteristics, applied sequence stratighy of carbonate ,buliding and analyzing the seismic faces of different sedimentary facies,by the seismic modeling studying and analying on oolitic beach reservoir's sersmic refective featrue, combination of well data, analyzing the trap of prediction,finding the gamma electrical measurement curves can diacrimination oolotic reservoir's lithological and the reservoir can produce significant attnuation at high frequency, explore a set method of carbonate ooitic reservoir's perdicting techniques, including seismic modeling and based on t the acoustic reconstruction inversion and frequency atteuntion gradient and "low-frequency shadow" technology analysis. Finally, integrate geological, drilling, seismic and other information, by PCA principal component analysis method the study area to abtain the integrated oolitic reservoir prediction.In one word, this article has made the following major achievements and understanding: in the aspect of methods and technology,①proposed the MIVMAS forward method to simulate the seismic response characteristics of oolitic reservoir, and the numerical simulation of the study area showed that the oolitic reservoir had "bright spot" reflection characteristics;②for the seismic response characteristics of oolitic reservoir , "middle-low frequency , non-cluttered and middle- weak continuity, strong reflection," proposed a forecast flow suitable for oolitic reservoir;③using the " low-frequency shadow" technology based on the high-precision time-frequency analysis, taking advantage of the low-frequency seismic signal information can be used to effectively predict the development of oil and gas area;④for the special development area of oolitic reservoir, the waveform classification based on self-organizing neural network can better achieve the division of the seismic- geological sedimentary facies. In the aspect of geological results,①by the seismic facies analysis based on waveform classification, classified the sedimentary facies of Feixianguan Group of the study area;②by the integrated prediction of a variety of methods, forecasted a favorable band of oolitic reservoir development area and carved out a favorable area (located at a relatively high structural position) and a less favorable area (in the relatively low structural position).All the analysis indicated that the above methods can better predict the distribution of oolitic reservoir and the favorable distribution area of reservoir, and can provide evidence for the deployment of drilling.
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