Study On The Influence Of Reservoir Configuration On The Distribution Of Remaining Oil After Polymer Flooding

In the period of high water cut,because of the difficulty of remaining oil increased,enhanced oil recovery can be widely used.But with a strong marine reservoir heterogeneity,due to the formation of different environments,different genetic sand body has different thickness,lithology and physical property heterogeneity.Combined with a long-term waterflooding,oil-water relationship is extremely complex,and the remaining oil distribution is complicated.Carrying out fine reservoir architecture research, analyzing the impact of reservoir architecture on remaining oil distribution after polymer flooding has an important meaning for determining the remaining oil distribution and accumulation characteristics,targeting to take different methods of mining remaining oil and enhancing oil recovery.Under the guidance of the theory of high-resolution sequence stratigraphy,reservoir geology,reservoir engineering,integrating core,logging,geology and the development of dynamic,etc,small layer of 204 wells of the Labei east block GII1-GII18 is divided into 21 units of deposition time in this article.The leading edge environment of the delta development in the objective layer in the study area is defined.First detailed study on unit of the configuration,then analyzed the internal features of different configuration units,the final analysis is the impact of configuration unit on remaining oil after polymer flooding.After the flooding,the remaining oil in the reverse rhythm reservoir is less than that in the positive rhythm reservoir.However,from the aspect of polymer flooding effect,it has the best effect on improving positive rhythm reservoir core,less effect on complex rhythmic core and worst on reverse rhythm reservoir.Judging from the position of the remaining oil distribution,after polymer flooding,the remaining oil is still focused on the part of poorer physical properties.The worse the physical properties of configuration unit was,the greater the thickness and the more remaining oil.Based on the study above,the main direction of remaining oil after polymer flooding is presented.Methods of remaining oil exploration are different in different configurations within a cell:subdivision injection and blocking high permeability aquifer can be applied in the remaining oil above underwater distributary channel;different batches of polymer flooding or three,two and multiple elements foam driving are fit in distributary channels and mouth bars which are higher permeable and thicker;suitable molecular weight polymers and fine separate-layer polymer flooding are chosen for sheet sand configuration unit;fracturing with the water cycle can be considered in distal bars and distributary bays which have the worstphysical properties and the smallest pore throats.