How many grains are needed for a provenance study?

Detrital provenance studies using single-grain geochronology are very labor-intensive. This paper presents a method for calculating k, the smallest number of grains in a sample that must be dated to achieve a required level of statistical adequacy. For example, if it is desired that no fraction of the population comprising more than 0.05 of the total is missed at the 95% confidence level, at least 117 grains should be dated. The paper also provides recommendations about cases where fewer than the optimal number of grains have been dated. (C) 2004 Elsevier B.V. All rights reserved.