Granulometric Analysis of Channel Sediments of Pedhi River, Maha-rashtra, India

Abstract

This study presents a comprehensive granulometric investigation of the channel bed sediments of the Pedhi River, a major tributary of the Purna River in the Amravati district of Maharashtra. The research aimed to analyse the textural characteristics and statistical parameters of these sediments to reconstruct their transport history and interpret the dynamic energy conditions of their depositional environment. During the dry season, ten sediment samples were collected at regular 5 km intervals to ensure a representative spatial distribution. Following standardised laboratory preparation and chemical treatments to remove organic matter, the samples underwent mechanical sieve analysis. Statistical measures, including graphic mean, inclusive graphic standard deviation (sorting), skewness, and kurtosis, were calculated using the formulas established by Folk to provide a quantitative basis for environmental interpretation. The results reveal that the Pedhi River sediments are predominantly composed of coarse to very coarse sand, characterised as moderately sorted and very fine-skewed. This suggests a consistent yet fluctuating energy regime, with a noticeable amount of finer material remaining trapped within a coarse sediment matrix. Most samples exhibited a mesokurtic distribution, indicating a balanced sorting relationship between the central grain sizes and the distribution tails. Bivariate plots and C-M patterns further validate a fluvial origin, indicating that saltation is the primary mode of sediment transport. These findings collectively point to a moderate-energy depositional environment where varied grain sizes were deposited simultaneously under the dynamic hydrological conditions of a meandering river system.