Objective
The structure of mantle convection drastically depends on the interaction between floating continents and mantle flows. This interaction leads to cyclic reorganisation of convection pattern which manifests itself in global geological features of the Earth. The effects of this interaction will be analysed assuming phase transitions and temperature-dependent viscosity and compute resultant geodynamical patterns. Continental and oceanic asthenosphere structures, large-scale stress distribution in the lithosphere, and formation of sedimentary basins will be studied.
The specific goals of the project are as follows: to model dynamics of convection pattern (whole-layered), to explain mechanisms of evolution of geodynamical structures (the asthenosphere under continents and oceans, subduction zones, marginal basins) and to calculate three-dimensional mantle flows and time-dependent distributions of density, temperature, and viscous stress; to develop a quantitative model of sedimentary basin evolution, and to construct a database with data from the Moscow syneclise, the Timano-Pechora and the pre-Ural pericratonic basins, to use it in the geohistory analysis, and to combine the resultant patterns of stratigraphy evolution with numerical modelling.
The model of mantle convection is based on equations of hydrodynamics and heat transfer with the minimum set of hypotheses and is self-consistent. Preliminary results show that solutions to these equations contain almost all main geodynamical structures, as mid-ocean ridges, subduction zones, marginal basins, and others. The models of basin evolution include accumulation of magmatic melt in the asthenospheric bulge, thermo-mechanical effects due to energy transfer and phase transition with density increase, and the flow induced by excessively heavy bodies. The numerical approach is based on an improved Galerkin-type method for unknowns approximated by bi-cubic splines.
Expected results will be the development of 3-D geodynamical models for the mantle with temperature and pressure-dependent viscosity for several continents floating on the mantle and having various parameters (their number, geometry, and initial positions). A calculation will be made of temperature, heat flux, viscosity, and stress (spatial and temporal distributions) under oceans and continents. In addition, a construction will be made of evolution patterns for three basins in Russia: the Moscow syneclise, the Timano-Pechora and the pre-Ural pericratonic basins, using the back-stripping analysis and numerical modelling.
Topic(s)
Call for proposal
Data not availableFunding Scheme
Data not availableCoordinator
55099 Mainz
Germany