Attribute Analysis And Oil-gas Detection Based On Generalized S-transform Of Synchronous Extrusion

As the depth of oil and gas exploration and development increases and seismic data collection is severely disturbed by the outside world,seismic data processing and interpretation personnel have become more difficult to identify oil and gas traps,oil and gas-bearing layers,and comprehensive evaluation of reservoirs.Oil and gas companies pay more attention to production,and oil and gas traps,reservoir connectivity,and fluid properties are one of the important factors that determine oil and gas production.Many scholars have found that the frequency attribute can better identify the reservoir's oil and gas,and can accurately describe fault information.In order to obtain more accurate frequency attribute information,it is necessary to develop high-resolution timefrequency analysis methods.The traditional time-frequency analysis method is affected by the uncertainty factors of Heisenberg,so its time-frequency focusing ability is limited,and it is impossible to achieve the fine description of the formation and the accurate detection of oil and gas.In this paper,based on the traditional time-frequency analysis method,a high-resolution time-frequency transformation method is studied.Through signal model analysis,the advantages and disadvantages of this method and the traditional time-frequency transformation method are demonstrated and applied to seismic data.In the identification of faults and the detection of oil and gas in reservoirs,the method is combined with the inversion results to verify the method,to illustrate the high precision and accuracy of the method for fine characterization of faults and oil and gas detection.The main research work of this article has the following contents:(1)Analyze and compare traditional time-frequency analysis methods such as Fourier transform,short-time Fourier transform,wavelet transform,S transform,and generalized S transform.It can be found that although the generalized S transform has a high time-frequency resolution,it is still affected by Heisenberg's uncertain factors,so that its time spectrum has a false frequency band.In order to further improve the time-frequency focus of the results of the generalized S transform,based on the theory of the generalized S transform,combined with the recent squeezing transform proposed by recent scholars,the research on the squeezing generalized S transform is carried out.Based on the derivation of the mathematical formula for synchronous squeezing generalized S-transform,and the time spectrum obtained by applying different timefrequency transform methods to the synthesized signal,the synchronous squeezing short-time Fourier transform,generalized S-transform,and synchronous squeezing generalized S The advantages and disadvantages of transformation and other timefrequency analysis methods.(2)Reservoir prediction first needs to carry out fault identification in the reservoir in order to find high-quality reservoirs.Seismic coherence properties have strong practicability in the interpretation of stratigraphic faults,but for complex fault zones,seismic coherence techniques will be limited by the low-resolution seismic data and the influence of background noise caused by stratigraphic conditions,making underground geology The information cannot be accurately identified.Therefore,this paper uses the high time-frequency multi-resolution technology of synchronous squeezing generalized S transform to spectrally decompose the seismic data volume to obtain single frequency data volume of different frequencies,and combines the multi-channel inclination steering coherence technology to perform coherent calculation on the single frequency data volume.The results show that synchronous squeezing generalized S-transform multi-frequency multi-angle dip steering coherent technology can effectively reduce the background noise caused by seismic data resolution and stratum occurrence.Multiresolution analysis of three-dimensional seismic data volume in a work area of the South China Sea using this method shows that the method is more beneficial to the fine characterization of small faults and the overall study of the fault system,which can prove the accuracy and practicability of the method.The characteristics of the fracture system in the reservoir proved by this technology will provide a basis for the subsequent detection of oil and gas properties.(3)Based on the actual seismic data,the generalized S transform and synchronous extrusion generalized S transform are used to analyze the oil and gas properties of the reservoir in the work area.The results show that: the two time-frequency transformation methods predict the oil and gas properties of the reservoir.significant difference.By comparing with the logging curve,it is found that the synchronous extrusion generalized S-transformation can more accurately identify the oil-gas bearing property of thin reservoirs,and can effectively detect the favorable areas of oil-gas bearing in the reservoir.(4)The low frequency shadow phenomenon of earthquakes is empirical and has multiple solutions.There is no mathematical formula derivation and a complete theoretical basis.Therefore,it is necessary to use other methods to verify the lowfrequency shadow results.The seismic inversion method has been developed for many years under the derivation of strict mathematical theoretical knowledge,and it is credible and accurate.Therefore,the results obtained by seismic inversion can be used to verify the accuracy of low-frequency shadow results.