Reserch And Application Of Reservoir Integrated Prediction Method In S Block Of Sulige Gas Field

Sulige gas field that the exploration area is about 40000km2, the Natural gas resources is 38000×108m3, Forecast reserves is 5336×108m3 is in the north-central of Ordos Basin, which is the largest oil find, the largest low-voltage, low permeability, low abundance of sandstone lithologic gas reservoir founded in china so far. Distribution of gas reservoirs affected by the structure is not obvious, mainly due to the control of horizontal sandstone distribution and reservoir properties change.The effective reservoir is coarse-sand rock that is in the braided river sandstone sedimentary, which is heterogeneity and poor continuity. Gas well production test is low and pressure drops fast. Not only the reserves controlled by single well is low but also stable production capacity is poor, so the development is difficult. The conventional single reservoir prediction technologies are hard to achieve an satisfactory effect. Therefore, we have to explore and establish some prediction schemes for gas-bearing sands and corresponding technical means that are suitable in this area, which can provide strong technical support for economic development in Sulige gas field.For these reasons, paper which uses "wave combined with seismic attribute, post-stack inversion combined with multi-wavelet decomposition and reconstruction techniques " as a prediction of gas-bearing sand in this area is based on the collection and analysis the results of previous studies.First of all, analysising the characteristics of seismic waveform in reservoir section and studying the seismic response model based on the fine layer of calibration; Studying the spatial distribution of reservoir characteristics and predicting the favorable sedimentary facies of reservoir by the use of 3D seismic attribute analysis, the time difference analysis tool. On the basis of that, quantitativly predicting the properties of sandstone reservoir through the post-stack inversion by well constrained. For the quantitative prediction of reservoir in he8 and shan1 of this area.First, from the characteristic that sandstone reservoir with low natural gamma but mudstone characterized by high natural gamma value, to exclude the impact of mudstone,we use the natural gamma inversion to identify lithology. Secondly, we further distinguish sandstone and dense-sandstone, so we can determine wether there are reservoirs and thickness of reservoir through the reservoir in the log response shown by the low-speed characteristics. Then in order to determine reservoir that is good or bad we use porosity inversion to predict reservoir properties. For the characteristics of gas-reservoir, using wavelet decomposition and reconstruction technology to predicte gas- reservoir. Overall, the reservoir prediction reflects a layer promoting and deepening idea, which is"Qualitation-quantitation, facies prediction-sandstone prediction-effective sandstone prediction-gas-bearing sandstone Forecast".