The Gas And Water Distribution Pattern And The Main Controlling Factors In Ma5 Member Of Tao2 Well Area,Sulige Gas Field

The reservoirs of the Ordovician Ma5 member of Tao2 well area in the Sulige gas field are mainly carbonate reservoirs with low porosity and low permeability.The heterogeneity of the reservoir is very strong and the continuity of the gas reservoir is poor.Gas and water distribution is complex and there are serious water production problems during the production process.So gas and water distribution pattern needs to be further studied.It is important to study the characteristics of carbonate reservoirs and gas and water distribution in this area.Detailed analysis of gas and water distribution pattern and controlling factors is greatly significant to further exploration and development of lower Paleozoic Ordovician reservoirs research.The characteristics of the reservoirs in the Tao2 well area were studied by core observation,cast slice,scanning electron microscopy and gas-water relative permeability.The research of gas and water geochemical characteristics was based on the data of gas components and water test data.Gas and water comprehensive identification method was used to judge the gas property of the reservoir.Test data and logging was used to analyze the distribution of gas and water and the main controlling factors.It is concluded that the main reservoir space of gas is dissolution pores while the physical properties of each layer are very different.The mineralization degree of normal water is mainly concentrated at 150?300g/L.Sedimentary environment is marine environment and gypsum-containing reservoir characteristics results in today's high water salinity.Gas component is mainly CH4 and it is classified to over mature dry gas type.Through the intersection diagram method and discriminant analysis method,it is effectively to identify the gas and water layer.The comprehensive recognition rate of gas and water layer identification is improved to 80%or more.The gas bearing content in the eastern area is stronger than that in the west.The gas reservoir is poorly connected and independent.Palaeogeomorphology,Tectonic action,bauxite distribution and reservoir heterogeneity are the main factors which have a certain influence on the distribution of gas and water.However,separated layer is the directed factor.Due to the strong heterogeneity of the carbonate reservoir,separated layer of poor reservoir property is.formed to space the gas and water in the reservoir.The reservoir is divided into multiple.gas and water units.The gas gathers in the upper part of the formation under the separation layer,and the water is concentrated in the downward direction in the same unit.