Tirekhtyakh, Arga-Ynnakh-Khai and Kester intrusive complexes based on the materials of GDP-200 on the territory of sheets Q-53-IX, X

The structural position, petrographic composition, petroand geochemical features of amphibole-biotite, biotite and amblygonite-lepidolite granitoid of the study area are characterized. Taking into account these characteristics, it is proposed that the intrusive formations of the Tirekhtyakh and Endegechuy tectonic-magmatic series belong to the Tirekhtyakh whereas intrusive formations of Yano-Borulakh belong to the Arga-YnnakhKhai and Kester complexes. The distinctive features of the Tirekhtyakh complex are the diorite-granodioritegranite trend of differentiation and the amphibole-biotite association of mafic minerals. Biotite and two-mica granite of the Yano-Borulakh series are assigned to the Arga-Ynnakh-Khai complex by the absence of diorite components in the differentiation trend and amphibole among mafic minerals. Small bodies and dikes of amblygonite-lepidolite granite and leucogranite with reverse trends of differentiation, the presence of lithium micas, the presence of topaz and the minerals of the amblygonite-montebrasite series, as well as high contents of lithium, phosphorus and fluorine, are combined into the Kester complex. Studies are recommended to clarify the age of igneous complexes using modern methods and justify the identification of the Tirekhtyakh complex with the Tirekhtyakh massif as a petrotype.