Research On The Technical Method Of Three-Dimensional Continuous Patchwork In Tabei Area

The 3D projects deployed in the Tarim Basin in the past only carried out seismic surveys for local geological structures in certain areas.The exploration report cannot analyze and study the distribution of underground structures and oil and gas reservoirs in a large area.It is necessary to connect the new and old 3D seismic data.In order to achieve a unified understanding of the geological laws of large areas.However,the equipment,technical parameters and polarities of different 3D project data collection cannot be completely consistent.There are large closure differences,energy differences,and wavelet differences between data in different blocks.With the progress of processing technology in recent years,According to the new processing geological task and geological target,determine the seismic data processing flow of Dalian sheet,optimization of static correction algorithm,noise suppression,consistency processing,matched filtering,residual amplitude compensation,pre-stack time migration imaging technology,pre-stack depth Targeted technical means such as migration technology and seamless splicing process can effectively eliminate the differences in energy,surface element,dip angle and wave group characteristics between different 3D seismic data,and at the same time,it is necessary to identify the overall fault combination and rock formation of the geological body.Sexual bodies provide objective and credible data.Experiments and studies are carried out in the areas of continuous patch static correction,noise suppression,amplitude consistency processing,wavelet consistency processing,velocity high-precision modeling,pre-stack time domain imaging,etc.sheet processing technology.In terms of static correction processing,the contiguous micro-logging constrained tomographic inversion static correction technology is applied,and the static correction amount is calculated uniformly in the whole area.Cannon first arrives at tomographic inversion,improving the accuracy of the entire inversion model.In terms of pre-stack denoising,for interference waves such as surface waves,shallow refracted waves,and abnormal amplitude value interference,which are different from effective waves in terms of frequency,energy level,and apparent velocity,step-by-step,frequency-division,and combined Multi-domain pre-stack fidelity denoising technology suppresses various regular and irregular interference waves.In terms of consistency processing,due to the different excitation and reception conditions of each block of 3D seismic data processed in contiguous pieces,the original data have certain differences in wavelet amplitude,frequency,phase,etc.On the basis,this difference between different work areas is eliminated through time-domain consistent concatenation processing.Surface consistency treatment is the best way to eliminate these differences.The spherical diffusion compensation technology and the surface consistent amplitude compensation technology are used to compensate the amplitude,so that the data energy in the work area can be coordinated vertically and horizontally.Apply surface-consistent amplitude compensation to eliminate horizontal and vertical inconsistencies in seismic data amplitudes.Due to the difference of the coverage times,the energy difference on the superimposed section is large.Through the amplitude processing technology based on the coverage times,the elimination of these differences is the energy balance.Amplitude attenuation,energy attenuation and frequency loss in the process of seismic wave generation are compensated by the application of micro-logging-constrained shallow Q-compensation technology.The seismic wavelet is corrected by using the surface consistent deconvolution to eliminate the influence of the surface inconsistency factor on the seismic wavelet,thereby enhancing the lateral stability of the seismic wavelet.Then,the main frequency of the seismic wave is further increased and the frequency band of the wavelet is broadened through the robust deconvolution of well control.In the aspect of 3D contiguous pre-stack time migration,the Kirchhoff integral pre-stack time migration method is used to improve the imaging accuracy of the target layer.The key parameters that affect the imaging effect of pre-stack time migration are migration aperture,dip angle,anti-aliasing Frequency operator,etc.In the aspect of 3D contiguous prestack depth migration,the small smooth surface on the surface is selected as the unified migration datum,the main velocity control layers are unified,and the anisotropy field is unified to obtain the control layer.The tomography method is combined with velocity iteration to gradually improve the velocity model accuracy from shallow to deep,making the offset space homing more accurate.