Cathodoluminescence of aragonitic gastropods and cement in Old Man Lake thrombolites, south-eastern South Australia

Abstract

It appears that differences in the signature of biogenic components and cements under cathodoluminescence may aid in the determination of palaeoenvironments in coastal areas. Living and recently dead aragonitic gastropods (Coxiella spp.) from Old Man Lake sediments luminesce bright apple‐green whereas the same species from the nearby saline environment of the Coorong Lagoon shows no luminescence. Following diagenetic alteration to calcite, as confirmed by X‐ray diffraction analysis, the gastropods show characteristic orange cathodoluminescence in both environments.