Mineral surfaces and their implications for microbial attachment:: Results from Monte Carlo simulations and direct surface observations

Our recognition of the crucial role that microorganisms play in a large variety of water-rock interactions at earth surface conditions requires an improved understanding and experimental quantification of the biotically modified or controlled processes. As a consequence, a combination of modeling techniques, experimental and field observations are developing into a promising strategy to approach this difficult task. This paper seeks to highlight some interesting questions and problems of microbial participation in mineral-water interactions and to present a modeling strategy that may help to study this exciting topic. Out of a voluminous body of work whose diversity of results underscores the complexity in the study of microbe-mineral interactions, we have chosen and briefly reviewed three recent experimental studies that have explored different aspects of the interaction between microbes and mineral surfaces. In the second part of this paper, we introduce a complementary approach that uses parameterized Monte Carlo simulations to explore and quantify crystal dissolution kinetics. This tool has already yielded considerable success in delineating abiotic water-mineral interactions, and we demonstrate here how it can be extended to the study of microbe-water-rock interactions. Finally, we discuss possibilities as to how this approach could be improved and simulation predictions tested in future laboratory work.