Upper Jurassic-Lower Cretaceous Sand Connectivity And Dominant Migration Path Of The Papuan Basin

The Papua Basin is a foreland basin formed by the compression stress of the Pacific plate at the junction of the Australian plate and the Pacific plate.The current exploration data indicate that the main reservoirs of the basin are Mesozoic clastic rocks and Cenozoic carbonate rocks.The Mesozoic clastic reservoir is mainly located in the western part of the basin.The lower Jurassic mud shale is a good source rock,and the upper Lower Cretaceous thick mudstone is a good cap rock.According to previous research results,the Papua Basin has experienced four stages: Gondwana Rift,Coral Sea Rift,Darai Lama,and Foreland Basin.The Mesozoic clastic reservoir developed in the Gondwana post-crack stage.In the foreland basin stage,an orogenic belt is formed in the eastern part of the basin,and a large number of faults and folds are developed in the western Papua fold belt of the orogenic belt,forming numerous anticline traps and broken anticline traps.In the research process,in terms of the Lower Cretaceous toro and Upper Jurassic Imburu group sand bodies,according to the single well report,the sand body thickness,sand ratio,physical properties and oil-bearing properties were analyzed.The correlation was analyzed and the transmission conductor connection was determined.The threshold value is established,and the sand body geometric connectivity evaluation model and the fluid connectivity evaluation model are established.Based on the theoretical of hydrocarbon migration,the registration and data of geographic information data are carried out on the geographic integration and spatial analysis modules of ArcGIS platform.In the research process,according to the analysis data of fluid inclusion analysis,hydrocarbon generation history analysis and thermal evolution history,the key moments of accumulation and accumulation are determined.Through the activity time of faults,tectonic stress analysis and statistical analysis of fault mud,determine The fault sealing property is combined with the distribution of reservoir sand bodies and source rocks to determine the matching relationship between fault-sand-source space,and the geological model is established based on the bottom structure of the caprock.The type of pressure during the accumulation period is analyzed,and the hydrostatic pressure is determined.Combined with the reservoir connectivity model and geological model,the migration simulation technology based on ArcGIS platform is applied to extract the superior migration path.Combined with the proven oil and gas distribution area,the results of the dominant migration path distribution are verified.The oil and gas accumulation area of the simulation results is in good agreement with the actual distribution.At the same time,the volume of the source rock and the reservoir reserves are calculated according to the simulation results,and there is a clear correlation.It proves that the connectivity model and geological model established in the early stage are reliable.