Textural features of igneous and metamorphic quartz as revealed by scanned cathodoluminescence (SEM-CL): Potential use in provenance studies.

摘要

Ubiquitous in most sediments and both chemically and mechanically resistant, quartz has long been used as a tool in provenance investigations. However, standard petrographic methods cannot reveal essential internal source rock characteristics. Conversely, Scanned Cathodoluminescence (SEM-CL) displays various textural features specific to source rock environment (plutonic, volcanic, metamorphic) that facilitates provenance identification of various sedimentary rocks, particularly fine-grained siltstones and mudstones.; In order to establish the preservation potential of CL textures through the course of the sedimentary cycle, a variety of source rocks from the Llano Uplift, central Texas and the Wichita Mountains, southwestern Oklahoma and their derived soils and stream sediments were examined. Survival of textures is apparent in the majority of larger quartz grains, however detection in grains smaller than sand size declines with decreasing size. Nonetheless, source rock textures are recognizable in a sufficient amount of finer-grained quartz to confirm provenance of siltstones as well as mudstones.