Changes in Reservoirs with Mid-low Permeability after Water Flooding and Analysis of Influencing Factors

The reservoir characteristic variation of Block Gao 6 was studied after water flooding,and the influential factors were analyzed.Combined the chemical analysis of coring well with dynamic production in different periods,after water flooding the porosity and permeability had a change for the better trend,but the reservoir heterogeneity was more complex.The strong water sensitivity become weak,acid sensitivity was enhanced;On the other hand,long-term water-flooding resulted in reservoir water salinity changes,changes were induce in logging response to the adjustment wells and deviation was caused in natural potential,resistivity rise.These changes are affected by reservoir characteristics,development mode and injected water,etc.Proper evaluation of the changes of reservoir characteristics is beneficial for the objective evaluation of reservoir flooded conditions,deepening the research on residual oil distribution,optimizing the perforation interval,adjusting the scheme of compatibility of injected water,well guiding the oilfield production,improving reservoir recovery.