THE ANABAR COLLISION SYSTEM AS AN ELEMENT OF THE COLUMBIA SUPERCONTINENT: 600 MA OF COMPRESSION (2.0-1.3 GA)

Abstract

The ancient cratons exposed at the surface (shields) and overlapped by sedimentary cover (platforms) are a mosaic of the accreted paleocontinents (microcontinents) transformed into tectonic blocks (terranes and composite terranes, superterranes-provinces) limited by collision zones (sutures or collision sutures). The Early Precambrian collision systems were formed as mountainous edifices of the Himalayan or Alpine types. At certain stages of the Precambrian geological history, the collision events embraced the entire globe and all sialic masses presumably gathered into one common aggregate that represented a supercontinent at that time. Thereby, collision, hummocking, and compression of terranes likely functioned continuously over the entire life of the supercontinent and its surface was overlain by platformal sedimentary cover. The extremely long compression of the crust was established in the Anabar collision system.