Compounded oil extraction microbe and its application in thickened oil and extra thickened oil exploitation

The invention relates to a new method to increase the recovery efficiency of thickened oil and extra thickened oil by using compounded oil extraction microbe, specifically speaking, the exploitation objects are the thickened oil with ground viscosity of greater than or equal to 5000 mPa.s and the extra thickened oil with ground viscosity of greater than or equal to 50000 mPa.s. The microbe with the compounded function is the mixed strain with special functions which is capable of substantially reducing the viscosity of the thickened oil and extra thickened oil and is selected from a laboratory. The compounded microbe, and an abundant carbon source-containing nutrient solution and an optimization agent are injected to an oil reservoir by a specific technology, the crude oil viscosity can be reduced by 50-95% by the integration effect of various active substances generated in the microbe metabolism process, thereby the fluidity of the crude oil can be increased to reach the purpose of raising the recovery effic