Research On The Structure And Reservoir Based On The Post-stack High-resolution Seismic Data In The Su 5 Block

Permian's Shanxi-Shihezi Formation is one of the major gas producing segment in Block Su5 located in the north-central part of the Sulige gas field,belonging to braided-meandering rivers deposit.Its reservoirs heterogeneity is strong,with changes in river migration.Due to the problem of effectively develop the small reservoirs in the Shanxi Formation of the gas-rich region in the southern Block and the serious water production in the new drilling wells outside the gas-rich area,the Block Su5 is facing difficult problem of stable production,with the continuous exploration and development work.In order to solve the above problems,this study combined the results of predecessors and used seismic,core,drilling,well logging and other data to make stratigraphic classification and comparison of the small layers of the Shihezi-Shanxi Formation on the Su5 block.The characteristics of sand body distribution were analyzed and the lithology and physical characteristics of the reservoir were studied.The reservoir porosity was distributed between 5 and 9%,and the permeability was distributed between 0.01 and 0.1 mD.The sedimentary facies control method was used to draw detailed sand body distribution maps,reservoir distribution maps,and effective reservoir distribution maps.The resolution of conventional seismic data is effectively improved by using post stack high-resolution processing technology.The high-resolution seismic data has the advantages of high matching accuracy with well data and high response characteristic to reservoir.High-resolution seismic horizon tracing is performed on the main sub-layers,and geological straifiation is verified,so that geological stratification and high resolution seismic horizons can be better matched.Using multiple seismic fault attributes,we first identify the faults in Block Su5,and put forward the new viewpoint that faults and fractures play a controlling role in reservoirs properties in Block Su5.Based on high-resolution seismic data,we finely interpret the structure of each sub-layer in the target formation.the structure map using seismic horizons is more accurate and has more details than the map just using well data.By means of multiple seismic attributes and seismic random inversion technology,the sand bodies and the quantitative reservoirs are predicted for each sub-layer of the target formation and the characteristics of sand bodies and reservoirs in each sub-layer are finely described.In view of the problem of more water production in the new drilling field,the gas&water distribution characteristics of reservoir are studied.The main controlling factors of gas and water distribution in the Shanxi-Shihezi formation in Block Su5 are analyzed by geological and seismic methods,and the distribution of gas&water in the block is predicted.Finally,combining reservoir characteristics,structural interpretation,reservoir prediction and prediction of gas&water distribution,a favorable target area for the next exploration and development of the gas field is put forward.