Elastic Character of Seismic Coda Envelopes Within East Indian Shield

Morozov, Igor B.; Safarshahi, Maryam

doi:10.1007/s00024-020-02600-2

Cited by 1 publication

(1 citation statement)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, waves recorded down to 0.05 Hz show resonant scattering properties due to strong interactions with large-scale velocity discontinuities of sizes comparable with seismic wavelengths (Cormier and Sanborn 2019). Strong scattering from the Moho (Sanborn et al 2017;Sanborn and Cormier 2018) and loss of energy due to leakage into the mantle (Wegler 2005;Margerin 2017) trade-off with the standard description of wave attenuation as a combination of scattering and absorption (Morozov and Safarshahi 2020;Nardoni et al 2021), making the application of any standard waveform-based tomography unfeasible.…”

Section: Introductionmentioning

confidence: 99%

Earthquake Characteristics and Structural Properties of the Southern Tyrrhenian Basin from Full Seismic Wave Simulations

et al. 2023

View full text Add to dashboard Cite

Modelling the response of seismic wavefields to sharp lateral variations in crustal discontinuities is essential for seismic tomography application and path effects correction in earthquake source characterization. This is particularly relevant when wavefields cross back-arc oceanic basins, i.e. mixed continental-oceanic settings. High-frequency (>0.05 Hz) seismic waves resonate and get absorbed across these settings due to a shallow Moho, crustal heterogeneities, and energy leakage. Here, we provide the first high-frequency wave-equation model of full seismograms propagating through realistic 3D back-arc basins. Inversion by parameters trial based on correlation analyses identifies P-, S- and coda-wave as attributes able to estimate jointly 3D Moho variations, sediment thickness, and earthquake source characteristics using data from a single regional earthquake. We use as data waveforms produced by the Accumoli earthquake (Central Italy, 2016), propagating across the Southern Tyrrhenian basin and recorded across Southern Italy. The best model comprises a deep Moho ($$\sim$$ ∼ 18 km) in the middle of the basin and a crustal pinch with the continental crust in Sicily. The deep Moho corresponds to the Issel Bridge, a portion of continental crust trapped between the Vavilov and Marsili volcanic centres. The Accumoli earthquake is optimally described at a depth of 7.3 km using a boxcar with rise time of 6 s. Our results show that the early S-wave coda comprises trapped and reverberating phases sensitive to crustal interfaces. Forward modelling these waves is computationally expensive; however, adding these attributes to tomographic procedures allows modelling both source and structural parameters across oceanic basins.

show abstract