Highlights—Garnet to the Source

Detrital garnet compositions provide a means to directly link sediment to the specific source rocks from which they are derived. In this paper, Hietpaset al. applied Mahalanobis distances, measured on canonical discriminant functions, as a metric to differentiate garnet compositions among potential sediment provenances. These metrics, applied to ~2,300 detrital garnet compositions isolated from modern river alluvium, successfully linked ~94% of the detrital grains to the source rocks from which they were derived. These results and methods illustrate a robust objective means to readily assess the complex, multi-dimensional detrital mineral chemical analyses. The method is also applicable to provenance studies relying on major and trace elements of other detrital mineral species. The results illustrate a means to constrain the lithology of source rocks and regional sediment provenance trends, insights valuable for understanding the unroofing history recorded in the stratigraphy of depositional basins.

Assessing detrital garnetchemical composition as a quantitative provenance tool: a multivariate statistical approach by Jack Hietpas, Scott Samson, Jacqueline Speir, and David Moecher