Grain size analytical and geochemical data of sediments from Ishakare and Alatan streams in Akungba-Akoko, Southwestern Nigeria

Abstract

The identification of anomalous elemental concentrations and the prediction of their dispersal pattern play a key role in geochemical exploration. Stream sediments are important focus in this aspect. Nine (9) sediment samples collected from Ishakare and Alatan Streams in Akungba-Akoko were subjected to grain size and inorganic geochemical analyses in order to determine their grain sizes distribution, travel distances, elemental concentrations and origin. Results of grain size analysis show that streams sediments are mostly medium-grained, poorly-moderately sorted and ranged from fine to strongly coarse skewed suggesting that they have been transported relatively not too far away from their sources under high to low energy. SiO2 is a dominant major oxide with concentration values ranging between 64.81 and 71.59 wt.% with a mean value of 68.07 wt.%. Abundance of Al2O3 indicates that samples are from Aluminum-rich source bed rock. The weights of Fe2O3 and TiO2 also point to gneissic rocks as a probable source. Generally, concentrations of trace elements were found to be low indicating that the contamination statue of the sediments ranges from unpolluted to moderately polluted