The Distribution of Several Trace Elements and Their Chemical Behavior in the Head-water Area of the Tama River

Abstract

The present paper deals with the distribution of trace elements and their chemical behavior in the head-water area of the Tama River using activation analysis.
The water samples were taken at 5 points in the main stream and 25 valleys flowing into it. The irradiated samples were made in the following ways: the elements inducing long life nuclides were prepared by evaporation to dryness and those inducing short life nuclides by coprecipitation method with Fe (OH), or Al (OH),
The activity of the irradiated samples were measured by 4096-channel PHA coupled with a Ge (Li) detector.
The analytical results are as follows: in the first place, the concentrations of Se, V, Co, As and Se were closely related to the geology of the areas through which the valley streams flow. Se content of streams which ran on the sedimentary rock formations was found to be 0. O^2- 0.09 ppb, whereas in streams on the igneous rock formations Se was not detected. Arsenic content of each streams on the igneous rock formations or the Jurrasic formations was found to be 0.6-1.4 ppb, whereas in strenms on the Cretaceous formations to be 1.7-2.3 ppb.
In the second place, Sb content had a close relation to the distance between the streams and the center of the metropolis rather than to the geology of the areas where the samples were taken, namely the shorter the distance, the higher became the Sb contents.