Abstract
We study the tectonic subsidence of the Timan-Pechora Basin by using a number of exploration wells and lithologic-stratigraphic sections along deep seismic sounding profiles. The tectonic analysis reveals a rapid phase of subsidence in the Late Devonian followed by a slower one, We suggest a two-phase model of persistent subsidence in the basin: (1) in the Ordovician (505-438 Ma B.P.), and (2) in the Silurian (438-408 Ma B.P.). The thinning of the lithosphere beneath the basin due to these rift phases led to the uplift of the asthenosphere and to partial melting. We explain the vertical motions of the crust by a magmatism-eclogitization model. The formation mechanism includes accumulation of magmatic melt below the lithosphere/asthenosphere boundary in the Early-Middle Devonian, a phase transformation of magmatic material to eclogites during the cooling, and a flow in the uppermost mantle induced by the evolved heavy bodies since the Late Devonian. We construct a two-dimensional numerical model of the flow in the asthenosphere, compute this flow and describe the resulting changes in surface topography. The model is in keeping with observed gravity, seismic, and subsidence data. Using the results of tectonic subsidence analysis and the model, we interpret the geodynamic evolution of the Timan-Pechora Basin and discuss the effect of eclogitization in the uppermost mantle on the basin development.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
