Department of Geology and Environmental Sciences Assistant Professor Wentao Cao co-authored a paper accepted for publication in Journal of Petrology, a top journal in the field of geology.
In the paper, “Petrological implications of seafloor hydrothermal alteration of subducted mid-ocean ridge basalt,” the authors examine the effect of hydrothermal alteration on the seafloor and its petrological implication on the fluid input in subduction zone. The basaltic portion of ocean floor could be altered by hydrothermal processes, such as spilitisation (Na-enrichment), epidotisation (Ca-enrichment) and chloritisation (Mg-enrichment). Thermodynamic modeling was applied to the extreme hydrothermally altered products in comparison to pristine oceanic crust along typical subduction geotherms.
The modeled results show that the hydrothermally altered products carry significantly more water into subarc to postarc depths than unaltered crust due to the enlarged stability fields of water (hydroxyl, strictly speaking)-bearing minerals toward deeper depth, Dr. Cao explained.
In general, this study indicates that hydrothermally altered basaltic oceanic crust could transport a significantly greater amount of surface water into deeper Earth than pristine crust. The manuscript can be viewed online.
Co-authors of the paper included David Hernández-Uribe, Richard Palin and Kim Cone, researchers from Colorado School of Mines and University of Oxford.
