Composition of sand samples from southwest and central areas of Transbaikalia
A study of the characteristics of the sand samples from the southwest shore of Lake Baikal has been carried out, with the purpose to find out the possibility of using the sand for the needs of the food industry. To determine the granulometric composition of the sand, a sieve analysis method has been applied, i.e. the separation of the granular mixture fractions using a set of sieves, with the further determination of the mass of each fraction and their percentage in the test substance. The sieving has been carried out by means of vibration. The X-ray analysis of the sand samples has used a Bruker D8 Advance diffractometer. The method allows determining the parameters of the crystal lattices, analyzing the phase composition of the test substance, and identifying the prevailing structures in the sample. Based on the x-ray analysis results, the crystal structure of the mineral components has been determined. The study has shown the following mineralogical composition of the sand. The prevailing mineral is quartz, its content varying from 40 to 60 percent; the content of albite and anorthoclase is 15 to 30 percent, and a small fraction is represented by dikkit and indialit (less than 5 percent). In the sand samples taken in the settlement of Angasolka, about 9 percent is represented by antophyllite. The processed results of the sieve analysis show the following. Most samples have been found to be quite homogeneous in terms of their grain composition, each sample having a predominant fraction, with the exception of the sample taken in the town of Slyudyanka, in which the particle size varies significantly. The studied sand samples can be classified as lacustrine or lake-glacial, their crystal-chemical composition being quite diverse. The study shows that the main components in the sand composition are quartz and feldspar, with a small content of other minerals being present. The granulometric analysis results show that the sand samples taken at the lakeshore in the vicinity of Slyudyanka are characterized by a large dispersion of the particle sizes, while other samples of the bulk material contain a predominant fraction. The sand from the Baikalsk area is most suitable for use in the food industry as it contains middle size fractions.