Microbial life in deep granitic rock

Abstract

In recent years, there has been rapid increease in the numbers of the published papers on aspects of the microbiology of subterranean environments. There has been a significant expansion in the understanding on microbial ecology in shallow ground water systems down to some 50-100 m, accurately reviewed by Ghiorse and Wilson (1988) and Matthess et al. (1992), and our knowledge is currently increasing about deeper crustal environments (Fredrickson and Onstott; 1996, Pedersen, 1993a, 1996; Stevens and McKinley, 1995). Deep subterranean environments vary considerably in composition, from soft sandstone and hardened sedimentary rocks to very hard igneous rock types. Here, microbial life in one of the hardest and most common rock types of the earth's crust, granite, is discussed.