Anabar Mountain Mass

Anabar Mountain Mass 

an extension of the Precambrian foundation (shield, anteclise) in the northern part of the Siberian Platform (on the middle and upper courses of the Anabar River and the upper courses of the Popigai, Kotuikan, and Arga-Sala rivers). Geographically, the Anabar Mountain Mass coincides largely with the Anabar Plateau. It is composed of a thick series of gneisses and crystalline schists of the Archean era (older than 2.3–2.5 billion years), broken by granitoid bodies (1.8–2.1 billion years old) and basic and ultrabasic rocks. The schists form large linear folds of northwest strike. Around the periphery of the mountain mass, on an eroded surface of Archean formations, gently sloping platform strata of the upper Pre-cambrian reef era (1.5 billion years old) and the Cambrian era are transgressively deposited.