Astrobiology December 2007, 7(6): 987-1005
http://www.liebertonline.com/doi/pdfplus/10.1089/ast.2007.0075
We examine means for driving hydrothermal activity in extraterrestrial oceans on planets and satellites of less than one Earth mass, with implications for sustaining a low level of biological activity over geological timescales. Assuming ocean planets have olivine-dominated lithospheres, a model for cooling-induced thermal cracking shows how variation in planet size and internal thermal energy may drive variation in the dominant type of hydrothermal system--for example, high or low temperature system or chemically driven system.