Studies On Textural Characteristics Of Jiadhal River Sediments, Dhemaji District, Assam, North East India

Research Article
Satyajit Sonowal and Jayanta Jivan Laskar
DOI: 
http://dx.doi.org/10.24327/ijrsr.2017.0811.1065
Subject: 
science
KeyWords: 
Sediments texture, channel bar, Jiadhal River, Dhemaji, Assam, N.E India.
Abstract: 

The Jiadhal river originates in the Himalayan mountains of the West Siang District of Arunachal Pradesh and subsequently debouches its sediments into the plains of the Brahmaputra River Valley in the Dhemaji District of Assam. Here the river acquires a braided and aggradational character and is characterized by extensive sedimentation. This paper investigates the textural characteristics of the channel sediments of the Jiadhal river in Dhemaji, Assam. The grain-size frequency distribution indicates a unimodal (i.e., sand) nature of the sediments, with the modal size ranging between 1ϕ and 3.5ϕ. The statistical size parameters (Folk and Ward, 1957) further indicate the sediments to be moderately sorted to well sorted (σi=0.43ϕ to 0.90ϕ), negative to very positively skewed (Ski = - 0.21ϕ to 0.35ϕ) and very platykurtic to very leptokurtic (KG=0.61ϕ to 1.98ϕ) in nature. The CM plot of the Jiadhal river sediments indicate transportation of the sediments by suspension, saltation and rolling.