The hercynian imposed deformations in the Golets Vysochaishii deposit structure (Baikal-Patom belt), ⁴⁰Ar/³⁹Ar data

Abstract

The paper presents the results of the detailed structural analysis and 40Ar/39Ar dating of the deformations in the Golets Vysochaishii deposit area. The geological and structural studies showed the folded-deformation sequence from large lying folds through axial-plane cleavage formation and cleavage to quartz-filled fractures. The 40Ar/39Ar dating of syntectonic sericite yielded the ages of two Hercynian tectonic impulses – 340 and 320 Ma. This stage is characterized by the earlier-known successive complication of the Early Paleozoic fold-nappe structure of the area. Analysis has been made on four samples taken from different sites and characterized by different sets of deformational structures. The 40Ar/39Ar age of 340 Ma reflects the formation of small-size folds as a result of interlayer sliding and sliding along the cleavage axial planes. The 40Ar/39Ar age of 320 Ma reflects the formation of discretely manifested crenulation cleavage and low-Au, low-sulfidation quartz veins oriented obliquely to the elements of bedding and axial-plane cleavage.