Procedia Earth and Planetary Science
Water-rock interactions play a critical role in the origin, existence, and prospects of life. Minerals are sources of energy and nutrients. Life uses aqueous chemical gradients to access and use minerals. Chemical disequilibrium, therefore, represents one type of biotic signature. Life also controls other types of disequilibrium, including isotopic disequilibrium and morphology. Water is a fundamental contributor to all of these biosignatures, acting as a medium for mass transfer and a reservoir for components. Distinguishing biosignatures from abiotic signatures challenges instrumental capabilities. Finally, the ubiquity and heterogenous distribution of life on Earth challenges the ability to interpret different types of disequilibria as evidence for life, or absence thereof.
astrobiology, geochemistry, detection of life
© 2013 Nancy W. Hinman
Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.
Hinman, N.W. Water-Rock Interactions and Life: Keynote Address (2013) 14th International Conference on Water-Rock Interaction, Avignon, France, 2013. Procedia Earth and Planetary Science, 7, 354-359.