Bakytgul’ B. Agaliyeva

This paper represents the results of a study of the chemical composition of salt lakes within the Burabay rock mass in eastern Kazakhstan. We sampled water and bottom deposits, geochemically analyzed the composition of the salt lakes, and performed aerial photography of the lakes to geometrize them. We studied the linkage between the rare-metal mineralization of granites of the Burabay rock mass and the salt lakes within the territory. Based on the obtained data, we identified the prospects of the survey area for rare metals. The surveys included 15 water samples and 15 bottom-deposit samples. To identify the source of salt in the lake water and deposits, the chemical composition of Burabay rocks was analyzed and seven samples of coarse-grained and porphyritic granites were selected. It was established that the water and bottom deposits accumulated elevated concentrations of valuable components (i.e., Sr, Rb, and U); this fact may be considered as an argument for conducting special surveys of small lakes in the region. The results obtained can be used for conducting further explorations and mining operations in the survey area in order to revive the rare-metal industry in the region, which will allow the development of new high-tech production and the creation of new jobs in this sphere.

The paper presents new geological, mineralogical, and isotope geochronological data for rare-metal pegmatites in the Kalba granitic batholith (Eastern Kazakhstan). Mineralization is especially abundant in the Central-Kalba ore district, where pegmatite bodies occur at the top of large granite plutons and at intersections of deep faults. The pegmatites contain several successive mineral assemblages from barren quartz-microcline and quartz-microcline-albite to Li-Cs-Ta-Nb-Be-Sn-bearing cleavelandite-lepidolite-spodumene. Ar-Ar muscovite and lepidolite ages bracket the metallogenic event between 291 and 286 Ma. The pegmatite mineral deposits formed synchronously with the emplacement of the phase 1 Kalba granites during the evolution of hydrous silicate rare-metal magmas that are produced by the differentiation of granite magma at large sources with possible inputs of F and rare metals with fluids.