Early permian age of nepheline syenites of the Korgere-Daba massif (Sangilen highlands, Tuva)

Abstract

This paper reports on geochronological U–Pb studies of baddeleyite from nepheline syenite of the Korgere–Daba alkaline massif, which is the largest massif within the Sangilen Highlands (Tyva). The established age of rocks, 295 ± 1 Ma, indicates that, in the Early Permian, undersaturation by silica magmatism occurred in the region in addition to the alkaline-granite magmatism (Ulug–Tanzek, etc.). This age furthermore points to the need to make corrections in the conceptions of a petrophysical type for the Devonian Sangilen complex, which is traditionally distinguished in this region. Until now, the Korgere–Daba massif has been considered in this regard.