Plate tectonic reconstructions of northern Asia: toward finding longitudes

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Paleomagnetism has always played a crucial role in plate tectonic reconstructions, aiming at obtaining paleomagnetic poles to build the Apparent Polar Wander Path (APWP) of different continents. Such paths are used to reconstruct position of continents in the past which is necessary to decipher how mantle convection relates to plate tectonics and how dynamical processes control seafloor spreading, volcanic activity, earthquakes, faulting and topography. All these dynamic processes control the geological environment for mineral resource formation, impact the climate change and evolution of life thus are important to understand. The APWPs are reliably reconstructed for some of the continental blocks and are very sporadic for others. At the same time, plate tectonic models based solely on paleomagnetic data are not able to restore paleolongitude information because of the axial symmetry of the geomagnetic dipolar field. Accurate absolute plate motion models, when both paleolatitude and paleolongitude can be reconstructed, are essential surface boundary conditions for mantle convection models. Large Igneous Provinces (LIPs), which are surficial expression of mantle plume activity of the past, and remnants of the subducted oceanic plates into the lower mantle were recently suggested and successfully used to perform a set of absolute plate tectonic reconstructions in Late Paleozoic –Mesozoic eras. At the same time, the plate tectonic models for this time interval for the Northern part of Asia (Siberia, North and South China) substantially differ as the number of paleomagnetic poles is insufficient and enormous time intervals do not have any reliable data. The Precambrian APWP for Siberia was not constructed at all. It explains why the reliability of the reconstructions for this part of the world is inadequate, although it occupies ~20% of all land mass on Earth. My research aims to build reliable plate tectonic reconstructions using new paleomagnetic data in order to assess assembly and evolution of the Northern Asia in the context of the global tectonic plate models. I propose to combine paleomagnetism and information on LIPs to evaluate paleolongitudes. Two antipodal hot mantle plumes, African and Pacific, dominate all present-day global shear-wave tomography models. The plumes correspond to the areas in the Earth’s mantle where hot deep mantle flows up. When LIPs are reconstructed to their eruption sites at least over the past 300 Myr, they appear to be concentrated above the edges of the two plumes. I propose to use the hypothesis about longevity of the mantle plume position in order to estimate the longitudes of the North Asian continents in the past. Accurate Asian plate tectonic reconstructions in the context of global reconstructions will be useful for all earth scientists who deal with the global scale geological processes. Paleogeographic maps carry the same importance for studying the past as any modern geographical or geological maps for studying present day phenomena therefore Canadian priority in this field of research is important. Mineral resource deposits belong to international companies and Canadian investments into exploration of ores and oil and gas deposits in Siberia are increasing exponentially. It is impossible to perform high efficiency exploration and mining in poorly studied regions. My research aims to improve such situations and to deliver to international and Canadian earth science community the plate tectonic aspects of Northern Asia.