Seismic Detection Method And Application Research Of Thin Interbedded Sandstone Reservoir

Thin interbedded reservoirs are an important reservoir resource.However,since the ability to apply seismic data to distinguish thin interbeds is limited,research on these types of reservoirs is particularly important.The use of geophysical methods to identify thin interbeds has always been a technical difficulty that geophysical workers need to pay attention to and break through.The thin interbedded layers of sand and mudstone are widely distributed in China and have a certain degree of distribution in many petroliferous basins.According to previous research results,the lithology and thickness of the thin interbedded sandstone mudstone vary greatly in the lateral direction,and because the seismic data has a small main frequency and a narrow frequency band,the researchers directly identify and distinguish from the seismic data.The thin interbed of sand and mudstone is difficult.Therefore,the use of seismic data to qualitative and quantitative identification of thin interbedded layers of sand and mudstone has important research significance and practical significance.Firstly,the high-resolution processing of the seismic data of the work area is carried out,and the inverse Q filtering and frequency division deconvolution method are adopted.At the same time,the thin layer model is designed to verify the effect of the two methods.By comparing the anti-Q filtering method Improve the resolution of seismic data better and apply it to actual seismic data;secondly,the Bayesian stochastic inversion method is analyzed in detail.According to the geological conditions and seismic data characteristics of the research area,the sensitive parameters optimization and Bayesian random inversion are carried out on the basis of fine-level tracking and interpretation.Characterizing the inversion profile of the thin sandstone reservoir of the target interval;then,in order to simulate the actual formation,several typical thin interbed reflection coefficient sequence models are designed,and the spectral characteristics of the designed reflection coefficient model are analyzed.In theory,the time domain and frequency domain of the reflection coefficient are theoretically performed.In order to further study the effects of the thickness of the thin interbedded single layer,the polarity of the reflection coefficient and the multi-interlayer reflection coefficient on the characteristics of the seismic wave waveform,the factors affecting the characteristics of the thin interbed seismic wave are studied in detail,by comparing the spectral features of the wedge-shaped model and the unequal-thickness medium model after S-transformation and generalized S-transformation,the generalized Stransformation method has superiority for improving the resolution of the timespectrum profile,and it is simple to identify the low-frequency shadows.Finally,the sand body thickness distribution map of the work area is obtained by inversion of the high-resolution seismic data of the research target area,and the low-temperature shadow phenomenon is applied to detect the oil-bearing property of the target interval by using the seismic time-frequency analysis method.The combination of the favorable oil and gas enrichment areas in the work area is realized.In this thesis,by using the generalized S transform and the Bayesian stochastic inversion method,the characteristics of the thin lateral sandstone reservoirs are difficult to identify,and the detection of thin interbedded sandstone reservoirs and the identification of hydrocarbon-bearing features are achieved,and the expected results are achieved.The prediction and evaluation of mutual sandstone reservoirs laid the foundation.