Sedimentologists use cathodoluminescence (CL) in clastic and carbonate petrography to reveal textural information that is not apparent with other (imaging) techniques. By studying grain provenance, sediment, and cement growth fabrics, CL studies provide insight to understand the diagenetic history better.

Cementation and diagenesis

Depositional grains and cement in carbonate and quartz minerals form under very different conditions that result in clear differences in their trace element chemistry. CL maps are useful to reveal the detail of the growth fabric zonation, dissolution, and micro-fracturing, including successive cement generations.

In sandstone, detrital (of various origins) and authigenic quartz overgrowths enable quantification of cement abundance and determination of porosity-loss processes.

Provenance

CL is a valuable technique to monitor the provenance of feldspars, mudrocks, and quartz (plutonic, volcanic, hydrothermal, and metamorphic). Specifically, maps can detect changes in crystal texture that correlate with impurity distributions and concentrations that approach parts per million levels.

References

Götze, J. M.; Plötze, M.; HaberMann, D., Mineral Petrol 71 (2001) p225 – 250

Scholonel, C.; Augustsson, C., Sedimentary Geology 336, 1 May 2016, p36 – 45

Color cathodoluminescence images captured using a ChromaCL2™ detector and provided courtesy of Prof. J Schieber, Indiana University Shale Research Lab.