466 RUSSIA Figure Tectonics of the Altai Sayan area (compiled by Yakubchuk) The mosaic pattern reflects significant strike slip faulting in the area The Main Sayan fault is a southern continuation of the Yenisei fault in the north that separates the Baikalides and Siberian Craton (Figure 7) Offset equivalents of the West Sayan and Tuva terranes are proposed in southern Transbaikalia The ‘Caledonides’ incorporate Neoproterozoic metamorphic terranes and Vendian to Early Palaeozoic magmatic arc and turbidite terranes In Russia, there are terranes of two Neoproterozoic to Early Palaeozoic arcs – Kipchak and Tuva-Mongol, overlapped by the Middle Palaeozoic Kazakh-Mongol and Rudny Altai and Late Palaeozoic to Early Mesozoic Orkhon-Selenga-Khanka arcs The Kipchak Arc includes the Salair and Batenev immature arc terranes separated by sutures with Vendian-Early Cambrian ophiolites from the adjacent Neoproterozoic terranes of Kuznetsk Alatau and Derba These structures are stitched by Cambrian to Silurian granitoids, but they are offset by the Kuznetsk-Teletskoye sinistral strike-slip fault for as much as 200 km In the north, the Variscan Tom-Kolyvan Terrane is thrust southward onto the ‘Caledonides’ It consists of flysch that might represent an accretionary wedge of an arc, presently hidden under the West Siberian sedimentary basin To the south and west, the ‘Caledonian’ island arc terranes are bound by the accretionary and forearc complexes of Gorny Altai and West Sayan They consist of Vendian to Silurian flysch with slivers of cherts, basalts, and Vendian–Early Cambrian ophiolites In the east, they have a T-shaped junction with the Main Sayan Fault, a continuation of the above-mentioned Yenisei Fault that strikes for more than 3000 km It truncates the accretionary terranes of West Sayan, and their dextrally offset equivalents can be found 600 km to the south-east in Transbaikalia South of the accretionary terranes are the ‘Caledonian’ terranes of Central Mongolia These are Precambrian metamorphic and Vendian-Cambrian immature arc terranes, known as the Tuva-Mongol Arc The arc starts near the Stanovoy ridge of the Siberian Craton and continues to the west It then turns to the south and east, forming the Mongol and then the Khingan oroclines The ‘Caledonian’ terranes are stitched by Cambrian-Ordovician and Silurian granites and Devonian calc-alkaline and alkaline volcanicsin Minusa, Rudny Altai, and other locations In the core of the Mongol Orocline are Neoproterozoic to Early Mesozoic accretionary wedges of the Khangai-Khentei Superterrane In Russia the superterrane is exposed in southern Transbaikalia, from where its analogues can be traced to the CircumPacific orogens via the Mongol-Okhotsk Suture In