Resolution of microearthquake mechanism inversions using a close-to-surface array at Ocnele Mari, Romanis

0423100 - GFÚ 2014 RIV RU eng C - Conference Paper (international conference)
Jechumtálová, Zuzana - Šílený, Jan - Trifu, C.-I.
Resolution of microearthquake mechanism inversions using a close-to-surface array at Ocnele Mari, Romanis.
Proceedings of the 8th International Symposium on rockbursts and seismicity in mines. Perm: Inter-YES, 2013 - (Malovichko, A.; Malovichko, D.), s. 175-180. ISBN 978-5-903258-28-4.
[International symposium on rockbursts and seismicity in mines /8./. Saint-Petersburg (RU), 01.09.2013-07.09.2013]
R&D Projects: GA ČR GAP210/10/1728
Institutional support: RVO:67985530
Keywords : alternative source models * moment tensor * shear-tensile source
Subject RIV: DC - Siesmology, Volcanology, Earth Structure

The resolution of small magnitude event mechanism inversions is studied using synthetic data as recorded by the actual seismic array installed at Ocnele Mari (Romania). Two alternative source models are employed: the moment tensor as a general dipole source, and a shear-tensile/implosion source model, representing a slip along the fault with an off-plane component. Noise level is simulated from low to high, and the analysis explores how the results are influenced by inverting P- and S-waves together, as compared to P-waves only. The orientation of the pure shear fracture component is almost always well resolved. On the other hand, the increase of noise distorts the non-doube-couple components of the moment tensor unless a high quality dataset is inverted. The shear-tensile/implosion source model yields considerably less spurious non-shear fracture components.
Permanent Link: http://hdl.handle.net/11104/0229207