Dynamic model of a coupled system of the convecting mantle, lithosphere and ice shield of Antarctica (MANTIS-II).

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Evolution of the Antarctic ice cup is extremely important for the human habitat, since it is directly related to the sea-level variations. It has been demonstrated recently that its behavior is strongly influenced by thermal regime and dynamics of the lithosphere. However, Antarctica remains one of the least studied continents with respect to the crust and upper mantle structure. Therefore, it is very important to employ continuously improving satellite data in new integrative models. In the proposed study we are going to develop a dynamic model, which describes interaction of the convecting mantle, lithosphere and overlaying ice shield of Antarctica. This model will be based on integration of the satellite gravity, interferometry and magnetic data together with seismic tomography and other geophysical information. The integrative model of the Antarctic lithosphere and upper mantle, which is developed at the first stage of the project, forms a basis for dynamic modeling of the coupled system. This 3D model provides variations of temperature, rheology and density, which are the input parameters for numerical simulations of the dynamic interaction between the convecting mantle and lithosphere. We will use recently developed computer codes, which implement such important parameters as for example 3D variations of viscosity, which depends non-linearly on several factors. First, this model explains structure, evolution and stress state of the Antarctic lithosphere. In particularly, evolution of the lithospheric roots in East Antarctica and of the rift systems in West Antarctica will be highlighted. Second, the coupled mantle-lithosphere model refines surface heat output and vertical movements strongly influencing the Antarctic ice shield, which dynamic behavior will be modeled in the following part of the project. Using of these parameters makes a principal difference from previous works. Furthermore, employing of various satellite data, showing current ice velocities, provides a possibility to constrain model parameters. The constructed model will help to explain behavior of the ice shield and to predict its future development.