Introduction

Geomicrobiology deals with the role that microbes are playing on Earth in a number of fundamental geologic processes in the present and have played in the past since the beginning of life. These processes include the cycling of organic and some forms of inorganic matter at the surface and in the subsurface of Earth; the weathering of rocks; soil and sediment formation and transformation; the genesis, transformation, and degradation of a variety of minerals; and the genesis, preservation, and degradation of fossil fuels.