Award Dates: September 1, 2013 — February 28, 2015
A laboratory experimental study was initiated to examine whether microtubules might form during low-temperature oxidative alteration of basalt by abiotic processes. Microtubules have been found in basaltic glass in core samples recovered the subseafloor, and these have been widely interpreted as products of biological activity. However, clear evidence for a biological origin of these microtubules has never been reported, and this project was initiated to investigate whether there are non-biological alternatives to the formation of the microtubules. To address this issue, several laboratory experiments were performed heating basalt glass with artificial seawater for periods of up to two months at 150°C. Thus far, however, the results have been inconclusive. Although no tubule formation was observed in the initial set of experiments, the extent of reaction in these experiments was very limited owing to closed-system conditions employed during reaction. Therefore, a new flow-through system that would more effectively simulate the open-system conditions of the natural system was constructed, and resulted in more extensive alteration of the basalt. Analysis of the products for the presence of microtubules is still underway.