A graphic method for depicting basin evolution and changes in the dominant hydrodynamic process from paleocurrent data

Abstract

Paleocurrent data measured on depositional elements and sedimentary structures (e.g., channels, cross-strata) are commonly utilized in the description of sedimentary strata. Paleocurrent data provide information about the depositional setting and in some cases can be useful for immediately detecting specific depositional processes (e.g., herringbone cross-strata for bimodal tidal currents). The typical graphical representation used to report paleocurrent data is the rose diagram. However, rose diagrams are not able to disclose all information contained in paleocurrent data, limiting the potentiality of such a representation method. In particular, there is presently no method to highlight changes in the paleogeographic configuration that can ultimately have an impact on the evolution of depositional processes and paleocurrent direction through time. Here, we present a graphic method that permits instant visualization of anomalies in paleocurrent distributions of the stratigraphic record that can be linked to changes in the paleogeography due to tectonic evolution or in the dominant hydrodynamic process. It is important to highlight that the proposed method does not aspire to replace rose diagrams but to provide an additional tool to be used before and in combination with rose diagrams in order to extrapolate as much information as possible from paleocurrent data.