Spatial variability of surface sediment basis on geostatistical analysis in the littoral area of Yellow River delta, China

A total of 155 surface sediment samples were collected from the littoral area of Yellow River Delta in 2007, and analyzed for texture and composition. Using geostatistic analysis, it is founded that there exist notable spatial autocorrelation of the clay and sand fractions in these samples with the autocorrelation scale being 44 km and 39 km, respectively. In comparison, the spatial autocorrelation of silt fraction is moderate, with the autocorrelation scale of 27 km. Analysis also reveals that the anisotropy of the sediment components is clear at the scale <20 km and >60 km and the distribution of the depocenters of sand fraction (i.e. content up to 40%) is very heterogeneous. Boundaries between these sedimentary units and their substratum are very sharp.