Structural Characteristics And Reservoir Prediction Of The Cretaceous Qingshuihe Formation In The Three-dimensional Block Of Dongdaohaizi

In the Crataceous period,Dongdaohaizi 3D block was located in the north and east of the hinterland of Junggar basin,which were interchange of two sources with good structural location and reservoir forming conditions and low exploration level,multi-phases sand bodies were developed,the adjacent area have great exploration potential which show rich oil and gas.By using fine structure interpretation of 3-dimensional and 2-dimensional seismic data in Qingshuihe formation in Dongdaohaizi 3D block and its adjacent area,working out the Contiguous structural map of target stratum.Analyzing the fracture distribution,the configuration and the evolution structural characterics.Utilizing the seismic inversion method,seismic attributes analysis method,strata slicing method,the spectral decomposition method and the 3D visualization method to predict the reservoir of the Qingshuihe formation in the 3D block.Based on the seismic method,optimizing the properties slices of target layer formation,analysing the shape changes of the sand bodies and the evolution of sedimentary.Based on the relationships between the trap identification and the development of reservoir,indicating the favorable exploration targets in Dongdaohaizi 3D block.There are two fault systems in the study area,the deep one and the shallow one.They are showing "Y" shape in seismic section,forming the beneficial hydrocarbon migration channels.By analyzing regional structural evolution,the Baijiahai uplift has experienced 6 phase tectonic movements,including the uplift phase and the subsidence phase.The strata slicing analysis shows that the early sand bodies of Qingshuihe formation at Cretaceous are well developed,which reflect the sendimentary characteristics of the lower Qingshuihe formation.The late sand bodies of Qingshuihe formation are well developed either,which indicate the sendimentaty characteristics of sandstones at the upper Qingshuihe formation.By using reservoir prediction,the low acoustic impedance sandstones of Qingshuihe formation in Crataceous are mainly distributed at the northwest of the Dongdaohaizi 3D block,and the boundary of lithological body is clear.Fault-block traps and lithologic traps development in the study area.There are 8 fault-block traps,1 lithologic trap in the 3D block,which have an area of 57 square metres.