Grain size/ Sediment Texture
The sediment texture/ grain size distribution pattern of sediment is a
potential indicator for discharge energy and environmental
characteristic (Visher, 1969; Friedman 1961, 1979; Glaister & Nelson,
1974; Sun et al., 2002). For the grain size analysis, 1 gm of samples
was treated with 10% HCl and 30% H2O2to remove the carbonates and organic matter, and other soluble salts.
The samples were thereafter dispersed with an ultrasonic oscillator for
10 min after mixing with a dispersant solution
((Na2PO3)6) (Yanhong et
al., 2006). The grain size analysis was done on a laser particle size
analyzer (LS 13 320) by Beckman Coulter with a size range of 0.004 -
2000µm. The grain size data was analyzed in the GRADISTAT program using
the Folk and Ward method in the phi (φ) scale. The GRADISTAT provides a
versatile way of representing standard and non-standard data giving a
range of graphical and statistical outputs like mean (φ), sorting (φ),
skewness (φ) and kurtosis (φ), and ternary plots (Folk and Ward, 1957;
Blott and Pye, 2001).