Submicron Raman spectroscopy mapping of serpentinite fault rocks

Submicron Raman spectroscopy mapping is able to unambiguously distinguish the main serpentine minerals within their in situ microstructural context. The high spatial resolution (similar to 370nm), large-area coverage (up to hundreds of micrometres in each dimension), and ability to map directly on polished thin sections allows novel interpretations to be made regarding the nature and evolution of serpentinite fault rock textures. The potential of this method is illustrated by examining submicron-scale textures of scaly serpentinites (e.g., dissolution seams, mineral growth in pressure shadows, distribution, and intergrowth of serpentine minerals) from a lithospheric-scale shear zone in New Zealand and a subduction-related serpentinite body in California, USA.