Structural Interpretation And Reservoir Prediction Of Block A In Zhaozhou Oilfield

Structural interpretation and reservoir prediction play an important guiding role in oil and gas exploration and development.Seismic interpretation can solve the problems in structural geology,and the results of reservoir prediction directly affect the effect of oil and gas reservoir development.With the popularization of 3D seismic exploration technology and the improvement of acquisition,processing and interpretation technology,high-resolution oil and gas exploration and development also put forward higher requirements for the accuracy of reservoir prediction.Combined well-seismic inversion is an important method to improve the accuracy of well-seismic reservoir prediction.Inversion methods,optimization of inversion parameters,quality control of well data on inversion process and fine structural interpretation are all key problems that restrict the effect of reservoir prediction.Block A of Zhaozhou oilfield is located in the southeast of Sanzhao sag.Affected by tectonic activities,the fault system in this area is extremely complex.In addition to a dozen major faults that control the reservoir,there are also a large number of secondary faults.More than 100 faults overlap and cut each other,making it difficult to interpret fine structures in this area.In addition,because the study area is located at the far end of the sedimentary system in the northern Songliao basin,the Putaohua formation is thin,the burial depth is deep,the sand-mud assemblage relationship is complex,and the horizontal distribution of sand between wells and the sand thickness prediction is difficult.The vertical resolution of seismic data is different from the thickness of reservoir,so it is necessary to choose an appropriate inversion prediction method according to the characteristics of the thin reservoir.In view of the above problem,this article is based on 3D seismic data and well logging data,the reservoir fine calibration technology,horizon of tracking technology,the breakpoint identification technology,the stratification and fault interpretation of the top and bottom of the Putaohua reservoir in the study area were carried out.The seismic attribute analysis technique is used to combine the faults in plane.At the same time,under the guidance of high-precision variable speed mapping technology,the initial structural maps of the top and bottom of the Putaohua reservoir in the study area were completed.The horizontal well stratification provided by Petrel software was used to restrict and correct the initial structural maps.Finally,the structural characteristics of A area,low in the north,high in the south and relatively gentle in the middle,were implemented.Based on the markov chain monte carlo stochastic simulation algorithm,the seismic waveform information and logging curves in seismic data are fully utilized for seismic waveform indication inversion.The inversion method realizes the idea of determining sedimentary facies under the tectonic background by analyzing the high frequency structural characteristics of the vertical lithology combination of the reservoir,and it is proved to be reliable by the statistics of the coincidence rate of theposterior well,which can solve the problem of predicting the thinner reservoir.Based on the inversion results of seismic waveform indication,the plane distribution of sand in 7 layers of the Putaohua formation in the study area was described.Reservoir prediction results show that the P141 layer development is relatively stable,in the whole plate shaped widespread distribution in the study area,P152 layer is mainly distributed in the central area,the thickness of sand and distribution range is also very handsome,P122,P13,P142,P16 layer is mainly a north-south extent belt development,P151 layer development.Finally,the correction of sand boundary and channel combination is completed by combining with logging facies map.