Using a GIS to enhance grain size trend analysis

This paper introduces GisedTrend, a plugin of the QGIS geographical information system that implements the Grain Sized Trend Analysis (GSTA) method. It is advantageous to incorporate the GSTA method in a GIS since it can directly access: (i) environmental information such as bathymetry, coastline, etc., (ii) spatial analysis tools available in such working environments, (iii) input/output data management; all these features are provided by standard GIS software. The paper also presents two case studies: the first case is based on an artificial dataset to focus on effects of obstacles on GSTA computed vector fields. The second case is based on a dataset acquired in the western part of the NW Mediterranean sea (Gulf of Lions, France). In this area, rocky formations, more or less continuous, outcrop directly on the seafloor, modifying the local hydrographic context and thus the sedimentary dynamic.