Fluvial contribution to the sediment budget of the Tay Estuary, Scotland, assessed using mineral magnetic fingerprinting

The sediment budget of the Tay Estuary, Scotland, UK, was evaluated using mineral magnetic fingerprinting. A multivariate unmixing model, based on constrained linear programming, permitted quantification of source contributions to the estuarine bottom sediments. Factor and multivariate discriminant analysis demonstrated that the two fluvial sources could be separated on the basis of five, linearly additive magnetic properties. However, lack of data dimensionality necessitated amalgamation of the two marine sources originally recognized. The model demonstrates the present-day dominance of marine bottom sediment derivation (78 ± 10%), whereas fluvial source contributions are 4 ± 10% from the River Earn and 18 ± 10% from the River Tay. The fluvial contribution should be considered in the context of the Tay being Britain’s foremost river in terms of discharge (long-term average ~ 167 m3 s-1). Source contributions to intertidal flat sediments collected over a spring–neap tidal cycle imply a temporal constancy to bed sediment provenance.