Reservoir Characterization And Geological Modeling Of Typical Multi-gas-water System Carbonate Reservoir In Central Sichuan Basin

The longwangmiao carbonate gas reservoir formation in M area is the first high-yielding,integrated gas reservoir,reservoir heterogeneity and the gas-water distribution complex discovered by Cambrian in Sichuan Basin.At present,there are relatively few studies on the fine description of gas reservoirs.In particular,there is no geological model to characterize the gas-water distribution,which affects the compilation and development of gas reservoir development scheme.Therefore,based on the analysis of the geological background and characteristics of the M carbonate reservoir,this paper based on the basic theory of gas accumulation and accumulation,uses the existing gas reservoir formation analysis method to carry out the gas accumulation.Based on the data of gas reservoir aggregation,a total of 46 conventional logging,42 imaging logging reservoirs and identification and interpretation of gas-water in Longwangmiao Formation of the study area were carried out.Based on the gas reservoir aggregation and the analysis data of 22-core,using the six-stage modeling method build 3D structural mode,3D sedimentary facies model,reservoir attribute model.The model of 3D gas/water contact model,3D fluid typing and zonation model and 3D gas saturation model in the study area were established,and the 3D geologic modeling of gas-water distribution in the study area was completed.The three dimensional spatial characterization and characterization of gas-water distribution of carbonate rocks in Gaoshiti-Moxi area are realized.The main conclusions are as follows:1)The results show that the main rock types in the study area are all kinds of granular dolomites,and the strata are deep and the diagenesis is complex and diverse,and it is subjected to multi-stage and multi-tectonic action.The reservoir space is complex and varied,and the reservoirs are associated with four kinds of reservoirs.The reservoir rocks,water,and water are developed during the long-term geological evolution.Gas interaction,resulting in a strong reservoir heterogeneity,gas and water distribution is complex,there is no uniform water and water interface,for the typical experience of repeated enrichment of the accumulation of gas reservoirs.2)Through the identification and interpretation of the Longwangmiao Formation,it is found that the conventional logging response characteristics of the reservoir are usually low gamma,low density,high neutron value and high acoustic time difference.The resistivity value is related to the physical properties and fluid The results show that the physical properties of the reservoirs are characterized by high permeability in the low porosity,low permeability,dissolution pore and fracture development section.The reservoirs are characterized by different characteristics.The relationship is clear,the overall performance of the lithology control of physical properties,physical and electrical properties reflect the characteristics of gas.3)Based on the six-stage modeling method,the structural model,the sedimentary facies model and the reservoir attribute model are established,and the geological framework and parameter field of the gas-water distribution modeling are established.On this basis,the 3D gas/water contact model,3D fluid typing and zonation model and 3D gas saturation model are established.The results show that the study area is mainly composed of four gas and water systems.The gas-water interface is composed of four different planes or surfaces,and the four-step steps are obvious.The gas saturation is divided into four system,and presents different characteristics.In this paper,the geological model of carbonate rock gas reservoir in Gaoshiti-Moxi area is established,and the heterogeneity of the whole gas reservoir in Longwangmiao Formation is described in detail.For the development plan and the zoning deployment,the well pattern is developed for different gas and water systems.It is of great significance to carry out targeted development and design,which can provide useful reference for the establishment of gas reservoir geological model.Compared with the traditional modeling method,the six-stage modeling method can be used to characterize the distribution of gas and water in the Longwangmiao reservoir,and the model is more reliable.