The SHIELD’21 deep seismic experiment, Ukraine

Abstract

<p>Carried out in 2021, the wide-angle reflection and refraction (WARR) SHIELD’21<strong> </strong>profile crosses, from SW to NE, the main tectonic structures of Ukraine. It targeted the structure of the Earth’s crust and upper mantle of the southwestern margin of the East European Craton with overlying Neogene Carpathian Foredeep and Vendian-Paleozoic Volyn-Podolian Monocline, Archaean and Paleoproterozoic segments of Ukrainian Shield and Late Paleozoic Dnipro-Donetsk Basin. The ~650 km long SHIELD’21 profile is an extension of previously realized RomUkrSeis profile carried out in 2014 and running from the Apuseni Mountains to the southwestern Ukrainian Shield (Starostenko et al., 2020). The WARR study along the SHIELD’21 profile using TEXAN and DATA-CUBE short-period seismic stations provided high-quality seismic records. The field work was performed during the summer of 2021, included the deployment of autonomous seismic stations and drilling-explosive works. A total of 264 seismic receivers were involved, (160 DATA-CUBE and 104 TEXAN stations). The average spacing between observation points is about 2.65 km. The sampling interval for all stations was 0.01 s. Seismic energy was generated at 10 shot points (SP) with total charge in all wells 5775 kg. The distance between the SPs was about 50 km.</p> <p>The main recorded seismic waves are the refractions of P- and S- waves in sediments, basement, crust and uppermost mantle, and reflections from crustal boundaries, Moho interface and boundaries in the uppermost mantle. The correlation picking of their arrival times will allow to build a velocity model not only for P-, but also for S-waves and Vp/Vs ratio.</p> <p>The main objective of the SHIELD’21 project is to get new seismic data that increase our knowledge on the lithosphere structure and geodynamics of the study region.</p> <p> </p> <p>Starostenko, V., Janik, T., Mocanu, V., Stephenson, R., Yegorova, T., Amashukeli, T., Czuba, W., Środa, P., Murovskaya, A., Kolomiyets, K., Lysynchuk, D., Okoń, J., Dragut, A., Omelchenko, V., Legostaieva, O., Gryn, D., Mechie, J., & Tolkunov, A. (2020). RomUkrSeis: Seismic model of the crust and upper mantle across the Eastern Carpathians — From the Apuseni Mountains to the Ukrainian Shield. Tectonophysics, 794, 228620. https://doi.org/10.1016/j.tec to.2020.228620</p>