Lithospheric Structure of the East European Craton at the Transition from Sarmatia to Fennoscandia Interpreted from the TTZ-South Seismic Profile (SE Poland to Ukraine)

• Published in: Minerals
• Main Authors: Tomasz Janik, Vitaly Starostenko, Paweł Aleksandrowski, Tamara Yegorova, Wojciech Czuba, Piotr Środa, Anna Murovskaya, Khrystyna Zayats, James Mechie, Katerina Kolomiyets, Dmytro Lysynchuk, Dariusz Wójcik, Victor Omelchenko, Olga Legostaieva, Andrzej Głuszyński, Anatoly Tolkunov, Tatiana Amashukeli, Dmytro Gryn’, Serhii Chulkov
• Format: Text
• Language: English
• Published: Multidisciplinary Digital Publishing Institute 2022
• Subjects: lithospheric/crustal structure; Moho; East European craton (EEC); East European Platform (EEP); Teisseyre-Tornquist zone (TTZ); Paleozoic platform (PP); Trans-European Suture zone (TESZ); wide-angle reflection and refraction profile (WARR); deep seismic soundings (DSS); Fennoscandia; Fennoscandian
• Online Access: https://doi.org/10.3390/min12020112

The TTZ-South seismic profile follows the Teisseyre-Tornquist zone (TTZ) at the SW margin of the East European craton (EEC). Investigation results reveal the upper lithospheric structure as representing the NW-vergent, NE-SW striking overthrust-type, Paleoproterozoic (~1.84–1.8 Ga) Fennoscandia-Sarmatia suture. The Sarmatian segment of the EEC comprises two crustal-scale tectonic thrust slices: the Moldavo-Podolian and Lublino-Volhynian basement units, overriding the northerly located Lysogoro-Radomian unit of Fennoscandian affinity. The combined results of the TTZ-South and other nearby deep seismic profiles are consistent with a continuation of the EEC cratonic basement across the TTZ to the SW and its plunging into the deep substratum of the adjacent Paleozoic platform. Extensional deformation responsible for the formation of the mid to late Proterozoic (~1.4–0.6 Ga), SW-NE trending Orsha-Volhynia rift basin is probably also recorded. The thick Ediacaran succession deposited in the rift was later tectonically thickened due to Variscan deformation. The Moho depth varies between 37 and 49 km, resulting in the thinnest crust in the SE, sharp depth changes across the TTZ, and slow shallowing from 49 to 43 km to the NW. The abrupt Moho depth increase from 43 to 49 km is considered to reflect the overlying lower crust tectonic duplication within the suture zone.