Prediction Of Reef Reservoir Of Changxing Formation In F Area,Northeastern Sichuan Basin

Now the world’s need for energy is growing,and thus makes the study of oil and gas exploration has very important significance.Reef reservoir occupies in the oil and gas reservoirs in a large proportion,therefore,the study of reef reservoir exploration is particularly important.Domestic and foreign scholars put forward a variety of methods for the prediction of reef reservoir,such as an earthquake seismic waveform classification phase analysis,seismic attribute analysis,seismic inversion method of analysis and other post-stack.The F region is between in the northeast of Sichuan Basin Watershed structure and the west of watershed structure,the target layer for Changxing formation of Permian Reef.Based on F in northwest gas field of 3 D seismic data as the foundation,for the region’s reefs reservoir buried depth,thin reservoir thickness,strong heterogeneity and complex internal and external structure,geophysical characteristics and changeful,and physical property of reservoir prediction is difficult and other characteristics,on the basis of the full collection and collation of F region drilling,logging,geology,the core and other information,the internal features and external morphology region reef reservoir,geophysical response characteristics,sedimentary characteristics and reservoir distribution started Research around F northwestern reef formations internal reflection characteristics,geometry and gas characteristics three research priorities,carried out research reef reservoir prediction and gas geophysical methods of identification,the use of targeted technical route of technical features and practical combination of conventional techniques,to identify northwest of Changxing reef reservoir and distribution of gas containing F regions and favorable development phase band for further oil and gas exploration area provided favorable in accordance with.The main contents and research of key results in the following areas:(1)Based on the regional structure and sedimentary background of the F area,the physical characteristics,seismic,logging response characteristics and sedimentary characteristics of the reef reservoir of Changxing formation in this area were analyzed and summarized(2)According to the original 3D seismic data in a narrow frequency band and random noise strong characteristics,the pixel filtering denoising method and spectral decomposition inversion method,effectively improve the signal to noise ratio and resolution of seismic data.In addition,the processed 3D seismic data describe the reef body internal structure and external form more clearer(3)In this paper,the geological model of the study area is established,and the forward modeling of the biological reef is carried out by using the forward modeling of wave equation,study the seismic reflection characteristics of the reef.(4)The seismic attributes analysis method(selected were root mean square amplitude attribute,Diapir(seismic reflection structure attribute)and the colored impedance inversion method(extracted the relative wave impedance)better predict the distribution of the reef reservoir.(5)By using waveform classification method and combining with seismic attribute analysis results,the seismic facies belts and sedimentary facies of the study area were studied,and the favorable facies belts of the reef reservoir in the study area are predicted.(6)Finally,the use of the spectrum of this article attenuation properties of the gas reservoirs were predicted,were extracted from the high-band frequency absorption coefficient properties,high frequency energy attributes,attributes the high band center frequency(peak amplitude)and Spectra spectral energy attenuation properties,by comparative analysis of the results of each attribute in the application area,preferably a spectra spectral attenuation properties of the study area gas distribution forecast.The thesis focuses on the internal reflection characteristics of the F region biological reef formation,geometry and gas-bearing characteristics of the three study focus,launched a reef beach reservoir prediction and Study on geophysical methods for identification of gas containing,is used for the combination of characteristics of technology and practical conventional technology,the technical route,find out the F region of Changxing Formation reef reservoir and gas distribution and favorable facies,provides beneficial basis for the area for further oil and gas exploration.