海上少井区基于井-震-动一体化的油气藏精细描述技术及应用实践OA

In recent years,with the improvement of exploration and development,offshore oil and gas fields have gradually entered the evaluation stage of potential reservoirs.However,the reservoir research of offshore oil and gas fields faces problems in general such as sparce drilling data,large burial depth,low resolution of seismic data,and thin reservoir thickness.Fine description of the reservoir in offshore areas with sparce wells has gradually be-come one of the main bottlenecks restricting the exploration and development.Based on relatively abundant drilling data,well logging data,high-quality OBN seismic data,and production dynamic data in the PH oil and gas field,we proposed a method of fine description of reservoir by integrating geology,logging,seismic,and reser-voir engineering in the P4-4 layer in the Oligocene Pinghu Formation as a case.First,based on the core facies,we determined that the P4-4 layer in the target area is dominated by distributary channel-crevasse sedimentary system of delta plain;combined with the modern sedimentary model,the sedimentary microfacies combination of distrib-utary channel-crevasse channel-natural levee-crevasse splay was proposed.Secondly,the single-layer fine correla-tion technology based on geological genesis was developed,the P4-4 layer was divided into four single-layer sand bodies,and the single-layer thickness was defined into 2 m in precision,and the vertical evolution model of dis-tributary channel-crevasse sedimentation was established.Thirdly,based on high-quality OBN seismic data,-90° phase shift and frequency-division RGB fusion technology was applied to characterize the distributary channel-crevasse splay sand bodies with different thicknesses.Finally,multi-data mutual verification among cores,single well profile,and inter-well correlation was conducted to realize semiquantitative to quantitative characterization of the distributary channel-crevasse splay sand bodies.Therefore,the rolling evaluation strategy of lithologic gas reservoir in the PH oil and gas field was proposed,based on which the deployment of Well X19 has been proved a successful breakthrough in lithologic gas reservoir field,presenting a meaningful guidance for the rolling evalu-ation of lithologic gas reservoir in other offshore oil and gas fields.