Abstract: An attempt has been made in this study to estimate the grain sizes and statistical parameters of aquifer sediments, in parts of Bayelsa State, South-South Nigeria. Precise measurement of statistical parameters of sediments is a vital and significant factor for the comparative evaluation of sedimentary depositional environment. Particle size analysis is a vital tool for the determination of the cost, quality and performance of aggregates for several economic purposes, such as in the construction, hospitality, agricultural industrial and of course in ground water resource management.