Mineral composition of eluvial and aeolian sands 
 (on the example of the unique collection of samples)

Abstract

The object of the research is the unique collection of samples of eluvial and aeolian sands collected in the tropical (Vietnam) zone and the zone with the temperate humid sharply continental climate (the Tunkinsk’s depression in the Baikal region). Traces of structural connectivity were established by visual inspection of the samples in laboratory conditions using a four-fold magnifier. "Cohesive" clayey (ps*) and ordinary sandy (ps) varieties were identified. The mineral composition of the collection sands was determined by the method of quantitative immersion analysis of the 0.25–0.05 mm fraction. The composition and morphological characteristics of various light and heavy terrigenous minerals were determined, and special coefficients were calculated using the method of quantitative immersion analysis. Beforehand, the granulometric analysis of samples was carried out using A.N. Sabanin's method. As a result, the fraction for mineralogical studies was isolated, and the content of sandy-pulverescent and clay particles was established. The research goal consists of a comparative analysis of the mineral composition of the sands, the degree of their chemical maturity, and the investigation of possible variants of structural connectivity formation.