Abstract

Serpentinized peridotite is actively reacting with groundwater in the subsurface in the Samail ophiolite in Oman. Although these rocks are partially to completely serpentinized, they are steeped in a groundwater aquifer containing hyperalkaline fluids rich in H production that can continue at low temperature, even after primary olivine and pyroxene are exhausted, thereby sustaining habitable conditions for microbial life.