Differences in microbial community composition between injection and production water samples of water flooding petroleum reservoirs

摘要

Microbial communities in injected water are expected to have significantinfluence on those of reservoir strata in long-term water flooding petroleumreservoirs. To investigate the similarities and differences in microbialcommunities in injected water and reservoir strata, high-throughputsequencing of microbial partial 16S rRNA of the water samples collected fromthe wellhead and downhole of injection wells, and from production wells in ahomogeneous sandstone reservoir and a heterogeneous conglomerate reservoirwere performed. The results indicate that a small number of microbialpopulations are shared between the water samples from the injection andproduction wells in the sandstone reservoir, whereas a large number ofmicrobial populations are shared in the conglomerate reservoir. The bacterialand archaeal communities in the reservoir strata have high concentrations,which are similar to those in the injected water. However, microbialpopulation abundance exhibited large differences between the water samplesfrom the injection and production wells. The number of shared populationsreflects the influence of microbial communities in injected water on those inreservoir strata to some extent, and show strong association with the uniquevariation of reservoir environments.