EUROPE/Timanides of Northern Russia 55 Neoproterozic, during deposition of the Timanian continental margin turbidites, development of the Pechora magmatic arc and Engane-Pe ophiolites, has been referred to in previous literature by several names, e.g., Palaeo-Asian, Turkistan, and Aegir, based on different interpretations of continent–ocean relationships The latter are not well constrained and the informal term Timanian Ocean is preferred here Towards the hinterland, the dominance in the Pechora zone of mafic to intermediate calc-alkaline igneous suites and volcanogenic sedimentary rocks has been interpreted to imply thrusting of oceanic domains onto the thick passive margin turbidites of the EEC margin (Izhma Zone) The western contact of the Pechora Zone is not well defined, but the presence of Timanian blue schists along strike, both to the southeast, in the northern Urals (Kvarkush) and to the northwest, in the easternmost Kanin Peninsula, suggests that subduction-related arc magmatism culminated in thrust emplacement onto the EEC margin The existence of microcontinental terranes (blocks) in the Timanian Ocean has been widely inferred (indeed, some authors regard the Timanides as a number of NW-trending aulacogens with oceanic crust separating continental blocks) The microcontinental terranes differ from the EEC by having Grenville-age signatures with a Mesoproterozoic metasedimentary succession intruded by ca 1000 Ma granites The oceanic character of the adjacent Pechora Zone favours the interpretation that these outboard terranes (e.g., the Bol’shezemel’skaya Zone, and perhaps the Novaya Zemlya metamorphic rocks at Sulmenev Bay) were not accreted to the EEC until the Vendian To the east of the Bol’shezemel’skaya Zone, Late Neoproterozoic ophiolites in the front of the Polar Urals (Engane-Pe) and calc-alkaline intrusions in some of the Uralian allochthons further east, provide the only evidence of the oceanic character of the most internal parts of the Timanide hinterland Taken together with the lack of evidence of the character of the Timanides east of the Urals, this has allowed the widely accepted hypothesis that Timanian Orogeny resulted from the subduction and accretion of Neoproterozoic ocean floor and island-arc assemblages, along with some fragments of continents (microcontinents), but without the involvement of a major Asian continent (e.g., Siberia) Continent–continent collision has not been favoured and the Neoproterozoic Timanian Ocean has been regarded as a forerunner of the Palaeozoic Uralian Ocean This attractive hypothesis remains largely unconstrained Timanian orogenesis was contemporaneous with the passive margin evolution of north-western Baltica’s Baltoscandian margin It was also approximately contemporaneous with orogeny in many other parts of the world; for example, the Baikalian along the margin of the Siberian Craton, the Cadomian of western Europe and the Pan-African of many parts of Africa and the Middle East Palaeomagnetic evidence has indicated that Baltica rotated about 120 counterclockwise between the Vendian and the Mid-Ordovician, prior to Caledonian collisional orogeny in the Silurian This evidence has prompted a variety of palaeogeographic reconstructions relating the Timanides to these other orogens It also implies that the rotation of Baltica may have accompanied the Timanian Orogeny, implying a significant component of dextral transpression during terrane accretion See Also Europe: East European Craton; The Urals Further Reading Belyakova LT and Stepanenko Vya (1991) Magmatism and geodynamics of the Baikalide Basement of the Pechora Syneclise Doklady Akademii nauk SSSR, (geologiya) 106 117 (in Russian) Bogatsky VI, Bogdanov NA, Kostyuchenko SL, Senin BV, Sobolev SF, and Khain VE (1996) Tectonic map of the Barents Sea and the northern part of European Russia: explanatory notes Moscow: Institute of the Lithosphere, Russian Academy of Sciences Moscow Cocks LRM and Fortey RA (1998) The Lower Palaeozoic margins of Baltica Geologiska Foreningens Forhandlin ger 120: 173 179 Cocks LRM and Torsvik TH (2002) Earth geography from 500 to 400 million years ago: a faunal and palaeomag netic review Journal of the Geological Society, London 159: 631 644 Dushin VA (1997) Magmatism and geodynamics of the palaeocontinental sector of the northern part of the Urals Moscow Nedra pp 211 (in Russian) Gee DG and Pease VL (2005) The Neoproterozoic Tima nide Orogen of Eastern Baltica Geological Society of London, Memoir Gee DG, Belyakova LT, Pease V, Larionov AN, and Dovzhikova E (2000) New, single zircon (Pb evapo ration) ages from Vendian intrusions in the basement beneath the Pechora Basin, northeastern Baltica Polar forschung 68: 161 170 Korago EA, Kovaleva GN, Ilin VF, and Pavlov LG (1992) Tectonics and metallogeny of the early Kimmeridgian of Novaya Zemlya, pp 196 St Petersburg: Nedra (in Russian) Lopatin BG, Pavlov LG, Orgo VV, and Shkarubo SI (2001) Tectonic structure of Novaya Zemlya Polarforschung 69: 131 135