Modelling the seismic response of the Mýtina maar volcanic structure

0572069 - GFÚ 2024 RIV DE eng J - Journal Article
Labuta, Martin - Opršal, Ivo - Burjánek, Jan
Modelling the seismic response of the Mýtina maar volcanic structure.
Earth, Planets and Space. Roč. 75, č. 1 (2023), č. článku 80. E-ISSN 1880-5981
R&D Projects: GA ČR(CZ) GA20-15818S
Institutional support: RVO:67985530
Keywords : ambient vibrations * site effects * 3D resonance * spectral analysis * 3D numerical modelling * Maar volcenic structure response * array measurements * dispersion curves * F-K analysis
OECD category: Volcanology
Impact factor: 3, year: 2022
Method of publishing: Open access
https://earth-planets-space.springeropen.com/articles/10.1186/s40623-023-01822-7

In this study, we determine the properties of the maar volcanic structure using ambient vibration analysis. We performed several ambient vibrations surveys at Mýtina maar (West-Bohemia, Czechia) to map amplification by site-to-reference spectral ratios and to estimate average shear wave velocities by array methods. As the maar diatreme is formed by a deep concave body of broken rock, strong 3D resonances develop. The site-to-reference amplification factors reach a value of 20 in the central part of the maar. Using the noise data, we demonstrate possibility of mapping the lateral dimensions of the maar infills by ambient noise measurements. To understand these observations, we developed a simplified 3D viscoelastic velocity model and simulated synthetic ambient vibrations by the finite difference method. The simulated response fitted both, measured fundamental frequencies and the amplification levels. The maximum depth of the crater was estimated to be at least 800 m.
Permanent Link: https://hdl.handle.net/11104/0342905