Trace elements as source indicators in cratonic sediments: a case study from the early Proterozoic Libby Creek Group, southeastern Wyoming

Considers how grain size and sorting affect trace element distributions in sediments. Similar REE distributions (LREE enriched, negative Eu anomalies), and most compositional differences can be explained by variable quartz dilution. With a few notable exceptions (Ca, Sr, Ni, and Cr), the matrix composition of the Early Proterozoic Libby Creek and Gowganda glacial diamictites, including REE distributions, agrees well with the average composition of Late Archean upper continental crust. Thus glacial diamictites may provide excellent indices of both relative and absolute major and trace element distributions in average upper crust. -from Authors