Age and tectonic setting of the Udokan sediment-hosted copper-silver deposit, Transbaikalia, Russia

The titanite age effectively dates the associated Cu sulfide mineralization. Since there is no evidence that titanite growth is appreciably younger than either the mineralization in the Medny area or the Udokan deposit as a whole, a ~ 1.9-Ga age for the stratiform Cu mineralization is considered likely. This age is undistinguishable from that of regional metamorphism during the collisional orogeny that led to final amalgamation of the Siberian craton and its incorporation into Columbia. The age also confirms Udokan as the world's oldest sediment-hosted Cu deposit and that its formation coincided with a continental-scale orogeny rather than with diagenesis and extensional basin development ~ 150 m.y. earlier.