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Deep structures and geodynamic processes in the present-day Tien Shanстатья
- Авторы: Nepeina Kseniia, Bataleva Elena, Rybin Anatoly
- Сборник: Proceedings of the 5th International Young Earth Scientists (YES) Congress “Rocking Earth’s Future”, 5th International Young Earth Scientists (YES) Congress “Rocking Earth’s Future” (Berlin, Germany 2019)
- Год издания: 2020
- Место издания: German YES Chapter, GFZ German Research Centre for Geosciences Berlin
- Первая страница: 1
- Последняя страница: 5
- DOI: 10.2312/YES19.04
- Аннотация: The Kyrgyz Tien Shan covers an area of intense intracontinental seismicity, for most earthquakes in southern Kyrgyz Tien Shan occur within the Indo-Eurasian convergence zone, and those in Eastern Kyrgyzstan mainly occur along major faults (Nikolaev line, Shamshi-Tunduk, Atbashi, Inylchek). The Tien Shan Orogeny occurred approximately 10 Ma (Jolivet, 2015). The upper-crust tectonic structures that formed during the intercontinental orogen of the Central Asian belt are of interest because existing modelling of these features is inaccurate and too general. Tracking of geological structures is key for robust geological reconstructions and geomechanical simulations, but distinction among individual crustal blocks is a complex task. Many researchers, when isolating crustal blocks, rely on their definition by fault positions and offset. Geological and geophysical studies have been used to define the characteristics of the block structure of the Tien Shan (Brunet, McCann & Sobel, 2017; Umirova, Istekova & Modin, 2016; Rybin et al., 2015; Bielinski et al., 2003; Thompson et al., 2002). Previous works explain the state of the lithosphere beneath Tien Shan using the petrology and electrical conductivity of xenoliths (Batalev et al., 2011; Bagdassarov, Batalev & Egorova, 2011). Here, we use the geophysical technique called magnetotelluric soundings (MTS) to extend the study of geodynamic processes and geological block description with physical parameters. In this paper we show that the MTS approach is beneficial for the characterization of underground structures in the Earth’s crust. Underground structures with different resistivity result in a distribution of electrical currents that can be measured with MTS soundings on the surface. This paper shows how the MTS technique can image geological structures up to 100 km depth as a geoelectric cross-section. The record of annual geoelectric variation confirms a relationship with the underlying geodynamic processes in the Earth’s crust (Bataleva, Rybin & Matiukov, 2019). The variations in geoelectric parameters are observed through geomagnetic measurements at geomagnetic stations or MTS profiles (Bataleva & Mukhamadeeva, 2018). It helps us to construct geophysical models of contemporary geodynamic processes. These contemporary geodynamic processes partly reflect the ongoing deformation of the orogenic system, specifically regional crust folding
- Добавил в систему: Непеина Ксения Сергеевна