THE SOUTH SIBERIA CENTRAL MONGOLIA TRANSECT

Studies of geological and geophysical data on the South Siberia- Centr al Mongolia geoscience transect which runs approximately along 100 deg rees E, show that the Asian continent was formed in the Phanerozoic by accretion of terranes most of which were microcontinents with Precamb rian basement. Suture zones separating the terranes are deformed and d eeply eroded magmatic arcs of different widths likewise classified as specific terranes. In these sutures, magmatic-arc rocks are locally as sociated with fore- and back-arc basin series. Most of the oceanic cru st has been subducted. The observed ophiolite belts are as a rule attr ibuted to the base of oceanic island arcs. The fragment of the Asian c ontinent traversed by the transect was formed through early, middle an d late Paleozoic stages of accretion.