Spatial Variation of Textural Parameters in a Small River: An Example from Khurar River, Khajuraho, Chhaterpur District, Madhya Pradesh, India

Abstract

Texture (grain size) is one of the many parameters, which is used in determining depositional environments of sediments and sedimentary rocks. In the present investigation, texture was analysed from sixteen stations in the Khurar River, Madhya Pradesh, India. Here, grain size analysis was carried out employing mechanical sieving method using a sonic shaker. Frequency and cumulative frequency curves were prepared from the grain size data on centimetre and arithmetic probability papers, respectively. The phi values were determined and used to calculate the statistical parameters such as mean, standard deviation, skewness and kurtosis. It is found that the mean size value varies from-0.63to 0.80 with a graphic mean distribution ranging from -0.27 to 0.40 ϕ, indicating that the size of the river sand is very coarse to coarse-grained. The standard deviation (sorting) shows a range of 0 .69 to 1.65 ϕ. The skewness values of the sediment samples range from 0.19 to 0.29 ϕ, thus, indicating the presence of fine fraction to near-symmetrical fraction in the population. The kurtosis varies between 1.03 and 1.09 ϕ, indicating that 25% of the samples are leptokurtic, 6.25% are very leptokurtic, 50% are mesokurtic and 12.5% are platykurtic. The platykurtic nature in few cases suggests mixing of sediments from two sources. Bivariate plots prepared combining various textural parameters were used to interpret their behaviour in the river sediments. C-M plot was also prepared to understand the dominant mode of sediments transportation in the Khurar River. In this river, all the sediments are dominantly characterized by the rolling process of transportation. This study reveals that sorting varies from poorly sorted to moderately well sorted in the course of the river may be because of dominance of winnowing and selective sorting in the lower reaches of the river.