With the advent of culture-independent, NGS-based microbial community analysis, environmental microbiology has opened up to research avenues hitherto only indirectly available. This includes the new field of geomicrobiology, investigations into the interaction between biological and geological/geochemical processes. Among ongoing research in this area is the study of the microbiotas of methane gas seepage pockmarks in the Öxarfjörður graben, where we investigate the impact of local geochemistry on the taxonomic composition of the microbiotas, and, using culture-based methods, bioprosect those microbiotas for bacteria with properties utilizable for bioremediation of petroleum-contaminated environments.