T2 Society of Economic Geologists Special Session: The Global Tectonic Setting of Ore Deposits—Present Understanding and New Advances II

Saturday, 26 October 2002
1:15 PM - 5:30 PM

METALLOGENY OF EURASIA: FROM BREAKUP OF RODINIA TO THE PRESENT

Paper number: T2-8
Program: Technical Sessions
Time: 4:30 PM – 5:00 PM

Authors

Abstract

Eurasia consists of Neoproterozoic to Cenozoic orogens and ancient cratons, which are fragments of the Neoproterozoic supercontinent of Rodinia. Their Archean - early Proterozoic basements host similar Au, BIF, Cu-Pb-Zn, Ni, and PGE belts. Laurentia was in the core of Rodinia rimmed by cratons of present Eurasia. Neoproterozoic active margins produced world-class Au and base metal deposits in the Baikalides. The subducting slabs formed a funnel that penetrated to the core-mantle boundary and caused ascending of the plumes that overheated the mantle underneath Rodinia and triggered its breakup in the end of the Proterozoic. Rodinia rmained in the center whereas the other cratons drifted apart. This caused assemblage of Gondwana and created Iapetus and Paleo-Pacific Oceans. The latter started as a backarc basin separated from the Paleo-Tethys Ocean by the cratonal terranes of Mongolia, which formed a basement of the magmatic arc attached to the Siberia and North China cratons. The active margins of Paleo-Tethys produced important Au and base metal deposits, especially in Central Asia.

Expansion of the Paleo-Pacific Ocean caused rotation of cratons and oroclinal bending and collision of adjacent magmatic arcs. By the end of the Paleozoic this produced the Altaid collage as a 'detached' fragment of Paleo-Tethys whose closure took place in the early Mesozoic to form Pangea.

At the Permo-Triassic transition, Pangea was surrounded by active margins of the Paleo-Pacific-Tethys with significant Au, base metal, and U deposits. The slabs again formed a mantle funnel that stimulated ascending the plumes, which produced Cu-Ni-PGE deposits in Siberia and caused subsequent breakup of Gondwana.

In the Jurassic to Cenozoic, Pacific-Indian spreading ridges propagated into Gondwana realm, India-Asia collision took place, and Eurasia formed. Several generations of magmatic arcs produced world-class Au, base metal, and other deposits of Eurasia.