Tectonic Overview of the Verkhoyansk-Kolyma Orogenic Region Andrei Prokopiev, Diamond and Precious Metal Geology Institute, Yakutsk, Russian Federation Jaime Toro, Dept. of Geology and Geography, West Virginia University, USA The Moma Range, Eastern Yakutia, August 1998 U.S.-Russia Joint Workshop on the Plate Tectonic Evolution of NE Russia STANFORD UNIVERSITY, DECEMBER 9-12, 2004
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Tectonic Overview of the Verkhoyansk-Kolyma Orogenic Region
Tectonic Overview of the Verkhoyansk-Kolyma Orogenic Region. U.S.-Russia Joint Workshop on the Plate Tectonic Evolution of NE Russia STANFORD UNIVERSITY, DECEMBER 9-12, 2004. The Moma Range, Eastern Yakutia, August 1998. - PowerPoint PPT Presentation
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Tectonic Overview of the Verkhoyansk-Kolyma Orogenic Region
Andrei Prokopiev, Diamond and Precious Metal Geology Institute, Yakutsk, Russian Federation
Jaime Toro, Dept. of Geology and Geography, West Virginia University, USA
The Moma Range, Eastern Yakutia, August 1998
U.S.-Russia Joint Workshop on the Plate Tectonic Evolution of NE Russia
STANFORD UNIVERSITY, DECEMBER 9-12, 2004
Outline• Review of the Verkhoyansk from N to S• Kular-Nera Slate Belt• Cratonal and Miogeoclinal Terranes
– Kolyma-Omolon, Okhotsk, Kotelnyi
• Island Arc Terranes and Ophiolites• Plutonic Belts• Paleomagnetic Review• Cenozoic Tectonics• Tectonic Reconstructions• Outstanding Problems
Geological map of the Verkhoyansk-Kolyma orogenic region
(after Tretiakov, 2004)
Middle Paleozoic grabens in the basement
(after Parfenov et al., 2001)
Main Tectonic Units of the Verkhoyansk-
Kolyma orogenic region
(after Parfenov et al., 2001)
Schematic Cross Section
Structural scheme of the Verkhoyansk fold-and-thrust belt
• Origin of the Baraya Salient• Priverkhoyansk foreland subsidence
Outstanding Research Questionsin the Verkhoyansk
• Mesozoic Shortening– Deep structure– Along-strike variation of structural style– Regional kinematics– Timing of deformation- thermochronology– Driving mechanisms for deformation:
• Collision/terrane accretion/subduction/strike-slip– Origin of magmatic rocks– Role of strike-slip deformation– Tertiary-recent tectonics
Outstanding Problems
The available tectonic models of Northeast Asia are incomplete and contradict one another (Fujita, Newberry, 1982; Parfenov, Natal’in, 1986; Zonenshain et al., 1990; Bogdanov, Til’man, 1992; Sokolov, 1992; Parfenov, 1991, 1994, 1995, 1996; Sengor, Natal’in, 1996; Nokleberg et al., 2000; Tectonics……, 2001).
• Kinematics of accretion
•Effect of inhomogeneity of the craton boundaries
•Relationship between the Pz and superposed Mz tectonic events
•Definition of subduction and collisional structures
The Growth of a Continent
Goal A Coherent Tectonic Model
Questions and Unsolved problemsQuestions and Unsolved problems
•Nature and age of paleo-oceanic basins east of the Siberian continent in the Late Paleozoic-Mesozoic (Oimyakon, South Anyui)
Tectonic Evolution
•Tectonic setting and age of Early Paleozoic arc complexes of the Alazeya upland.
•Nature and age of metamorphic complexes at the basement of the Omulevka and Prikolyma terranes.
•Problem of outlining an Early Paleozoic active continental margin along the eastern edge of the Siberian continent.
•Tectonic setting, age, and inner structure of ophiolites
Questions and Unsolved problemsQuestions and Unsolved problems
•Where is the accretionary wedge complex between the Verkhoyansk foldbelt and Kular-Nera terrane and the Kolyma-Omolon microcontinent?
•North collision with Kolyma-Omolon microcontinent
•South accretion along Okhotsk margin
Can we distinguish structures and magmatism due to these two synchronous processes?
Accretionary Tectonics
Questions and Unsolved problemsQuestions and Unsolved problems
Evolution of Sedimentary Basins
Setting and evolution of Late Pz and Mz basins surrounding the Kolyma-Omolon microcontinent
(Polousnyy, In’yali-Debin synclinoria, etc.).
Rift? Accretionary Prisms? Syn -collisional? Post-collisional?
Determination of source areas and links.
Links between basin evolution and tectonic/magmatic events
Sedimentological and geochemical characterization
Questions and Unsolved problemsQuestions and Unsolved problems
•Geodynamic setting of the Main and Northern Granite Belts?
Volcanic Arcs and Magmatic Belts
•Mantle plumes and their role in Late Mesozoic geodynamic events.
•Paleozoic and Early Mesozoic volcanism on passive and active continental margins.
•In what direction did the subduction zone dip between N. Asia and Kolyma-Omolon?
Questions and Unsolved problemsQuestions and Unsolved problems
•Recognition of Proterozoic and Mid-Paleozoic rift events in the Kolyma region
Role Extensional Tectonics
•Mechanisms for large-scale extension in the Indigirka belt.
•Are there metamorphic core complexes in the Okhotsk, Omolon, Omulevka and Prikolyma terranes?