In this work, we describe an experiment concerning global–local full-waveform inversion, carried out on a P-wave seismic reflection profile that was acquired at Luni, an archaeological site in Italy. The global full-waveform inversion makes use of the two-grid genetic algorithm scheme and recorded refraction and diving waves, to build an initial velocity model of the subsurface. Two important pieces of a priori information which help to better constrain the inversion results are the refraction velocity model and the Dix-converted semblance velocity field obtained from time processing. A good match between observed and predicted data allows us to use the estimated velocity field as the starting point for a local, gradient-based full-waveform inversion that inverts the recorded data (except the surface waves). The final estimated velocity field shows two main discontinuities: one is very shallow and related to the refractor velocity model used and the other corresponds to the strongest reflection event observed on the pre-stack depth-migrated section, at a depth of 100 m. The pre-stack depth-migrated common image gathers provide evidence of a good hori- zontal alignment of this reflection, indicating an accurate velocity estimation down to 100 m depth that corresponds to the maximum offset used in the acquisition.

Acoustic global‐local FWI for p‐velocity estimation of near‐surface seismic data acquired in Luni, Italy

Stucchi, Eusebio;Pierini, Silvio;Tognarelli, Andrea;
2020-01-01

Abstract

In this work, we describe an experiment concerning global–local full-waveform inversion, carried out on a P-wave seismic reflection profile that was acquired at Luni, an archaeological site in Italy. The global full-waveform inversion makes use of the two-grid genetic algorithm scheme and recorded refraction and diving waves, to build an initial velocity model of the subsurface. Two important pieces of a priori information which help to better constrain the inversion results are the refraction velocity model and the Dix-converted semblance velocity field obtained from time processing. A good match between observed and predicted data allows us to use the estimated velocity field as the starting point for a local, gradient-based full-waveform inversion that inverts the recorded data (except the surface waves). The final estimated velocity field shows two main discontinuities: one is very shallow and related to the refractor velocity model used and the other corresponds to the strongest reflection event observed on the pre-stack depth-migrated section, at a depth of 100 m. The pre-stack depth-migrated common image gathers provide evidence of a good hori- zontal alignment of this reflection, indicating an accurate velocity estimation down to 100 m depth that corresponds to the maximum offset used in the acquisition.
Stucchi, Eusebio; Pierini, Silvio; Tognarelli, Andrea; Brunod, Jimi
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11568/1040950
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 1
  • ???jsp.display-item.citation.isi??? 1
social impact