Sediment grain size

Abstract

Sediment grain size is considered one of the most important tools for the interpretation of depositional environments in estuaries (Das, 2009). Sorting indicates the process of modification of the sediments, whereas graphic mean size reflects the environment of sediment accumulation. Rigorous flow transports the sediments in the depositional environment causing poor sorting of sediment particles. Sediments are skewed in selective transportation, and a particular sediment population is characterized by inclusive graphic kurtosis (Davis, 1983). Grain size of estuarine sediments reflects the nature of source sediments and their hydrodynamic condition of deposition. Generally erosion dominates along the seaward reach of the estuary, with high wave energy and deposition predominating in the landward reaches of relatively quieter environment. Thus finer muddy sediments are deposited on the estuarine banks and flanks of the mid-channel bars and point bars, with low depositional energy.