Relief evolution and formation of placers (with special reference to South-Eastern Priokhotye)

Abstract

During Oligocene stage of regional planation the releasing of minerals from the host rock took place. During Neogene stage of dissection the transportation of metal from crust of weathering and its concentrating in alluvial deposits happened. Repeated interchanges of planation and dissection of land surface in Late Pliocene as Quaternary time led to rise and enrichment of placers. Early-Pleistocene epoch of cutting has more productive alluvium than later epochs, maximum ore concentration exists in the areas where placers of different age are overlapped. Morphology of gold in the recent placers indicates that significant part of metal have migrated long distance after the primary source had been destroyed.