Relative sea-level reconstructions by using foraminiferal transfer functions

Transfer functions, that use benthic foraminifera, are widely applied for reconstructions of changes in paleoenvironments such as relative sea-level changes and tectonic-induced vertical coastal motions. Such reconstructions are based on a representative modern training data sets, often sampled along the environmental gradient to be reconstructed. The species-environment relationships in a training data set can be modeled by using an adequate numerical technique, and the resulting transfer function model can then be applied to a fossil data set to reconstruct paleo-environmental conditions such as relative sea-level changes. Although transfer functions models are relatively easy to develop and to apply, several studies have shown that there are also difficulties with this approach. This study describes and discusses various aspects that should be considered when using the transfer function approach for relative sea-level estimates. It concentrates on the modern species-environment relations with a special focus on marine environments, describes widely used numerical methods for transfer function development, discusses several validation methods and addresses applications.