Detrital geochronological analyses, combined with information on river sediment load, are widely employed to constrain erosion patterns in orogenic belts. Major assumptions in most detrital studies are that detrital samples are fully representative of eroding bedrock, and variation in original mineral concentration, often referred to as fertility, is negligible. Nevertheless, hydraulic sorting effects during transport may strongly affect sediment composition, and mineral fertility strongly depends on bedrock lithology.

In this detrital geochronology study, we illustrate how hydraulic sorting effects can be properly evaluated, and how mineral fertility in bedrock can be determined from detrital samples, in order to infer reliable...