The Research Of High-resolution Post-stack Inversion Methods And Application In Tahe Oil Field

As the exploration of oil and gas become more and more extensive, it become more and more difficult to find new oil and gas, the emphasis of exploration has been transferred from the reservoirs easy to find such as structural reservoirs to complicated reservoirs such as lithology and thin bed. Because of the limitation of seismic data resolution, the accuracy of reservoir prediction and the ability of identifying thin reservoirs are limited. The inversion technology can connect the high resolution of the vertical logging data and the lateral continuity of the seismic data, so it has become the most important technology in reservoir prediction.The seismic inversion can be divided in to post-stack and pre-stack inversion according to the different application data, and the post-stack inversion has been used more extensively for its maturity. The original studies the development situation of various post-stack inversion methods and choose the integral inversion, recursive inversion, inversion based on model and the frequency-divided inversion to do extensive theoretical study and relative merits analysis, and choose representative methods to do practical application research in Kalashayi series clastic reservoirs in Tahe oil field.The exploration of Tahe oil field has great potential and foreground, but because of the complexity of reservoir and the seismic data quality cannot satisfy the requirement, the development of exploration is limited. According to the characters of the research work area, finish the zero-phasing process of the seismic data, logging data process, layer comparison division, fine structure interpretation, target curve rebuilt based on the SP curve. And based on these work finish the sparse spike inversion, geostatistics inversion and frequency-divided inversion experiment, compare the different results of the various methods and do analysis.Through comparison of the practical applications, we can find that the sparse spike inversion has low resolution, high correlation with seismic data and stable inversion result, but cannot meet the requirement of flaggy resolution. This method is proper for the situation in which there is less logging data and the result can be the vertical limitation of the geostatistics inversion process. The geostatistics inversion method in take the information of geostatistics, connect thoroughly the seismic inversion method and Stochastic simulation Theory, the results can be used in flaggy resolution, which integrate the lateral resolution of seismic data and the vertical resolution of logging data. This method has the model, low correlation with seism, and the result has multiplicity, can lead to several random results, so the risk estimation is needed according to practical geology, Frequency division inversion is a new method that connects the wavelets decomposition technology, supporting several theories such as the vector machine algorithm and AVF principle, the results are not influenced by the wavelets, having high correlation with seismic data, high resolution, meeting the requirement of flaggy reservoir. So the method has high value of raising the accuracy of the reservoir.