The Study On Pre-stack Merge Processing Technology Of Offshore 3D Seismic Multi-blocks

Conventional 3D geophysical exploration,due to limitations in exploration tasks,geological targets,acquisition design,acquisition technology,capital investment,etc.,the area of single 3D survey block is relatively small,and the cross-border structure of the joint between the 3D survey block is not conducive to interpretation,the oil and gas potential of the combined area has not been fully explored.As oil and gas exploration deepens,more hidden reservoirs need to be discovered,especially the potential of the joint sites in adjacent 3D block areas.However,because these survey areas are acquired under different acquisition conditions,the energy,phase,frequency and signal-to-noise ratio of each blocks are different which cannot be interpreted and studied in a unified way.Bohai Oilfield is an important oilfield producing area in China,and exploration and development has entered a mature stage.Based on the background of large-area 3D seismic data pre-stacking in Bohai Sea,this paper summarizes a set of process flow,merge policy and key processing techniques which are applicable to large-scale,multi-blocks offshore.By applying the techniques and methods of observation system consistency processing,time difference consistency processing,energy consistency processing,phase consistency processing,frequency consistency processing and other techniques and methods,the pre-stack merge processing of 3D offshore multi-blocks is realized.Through the actual production and application,the result of 3D pre-stack merge processing is obvious,and the differences in energy,phase and frequency between different blocks can be eliminated,the imaging of transboundary structures are improved;the data quality is optimized and the effective frequency band is broadened.The merge processing of multi-blocks can provide favorable basis for the overall evaluation of exploration areas,solve the geological problems faced in exploration,and the processing effect is satisfactory,which is worthy of further reference and application by other exploration areas.