Toward a Practical Appraisal for Waveform Tomography of Band- and Offset-Limited Marine Seismic Data
| Autor: | César R. Ranero, C.E. Jiménez-Tejero, Valentí Sallarès, Adrià Meléndez, Claudia Gras |
|---|---|
| Přispěvatelé: | Ministerio de Economía y Competitividad (España), Ministerio de Ciencia, Innovación y Universidades (España), Agencia Estatal de Investigación (España) |
| Jazyk: | angličtina |
| Rok vydání: | 2021 |
| Předmět: |
Offset (computer science)
Travel time tomography Velocity models Downward continuation Marine seismic data Waveform tomography Full waveform inversion Acoustic waves Signal analysis Numerical modelling General Earth and Planetary Sciences Waveform Tomography Electrical and Electronic Engineering Inverse theory Geology Seismology |
| Zdroj: | Digital.CSIC. Repositorio Institucional del CSIC instname |
| Popis: | 14 pages, 13 figures, 1 table.-- This is a contribution of the Barcelona Center for Subsurface Imaging that is a Grup de Recerca 2017 SGR 1662 de la Generalitat de Catalunya We present a generalized workflow to retrieve high-resolution P-wave velocity ( VP ) models of complex Earth’s subsurface structures from traditional marine near-vertical seismic reflection experiments. These records have typically offsets too short to map refraction phases and lack low-frequency information. The workflow is composed of three steps: 1) downward continuation (DC) of seismic records to the seafloor to recover diving wave information; 2) travel-time tomography (TTT) of first arrivals obtained from DC data, to retrieve a kinematically correct model; and 3) full-waveform inversion (FWI) of the original streamer dataset, starting with the model obtained with TTT and sequentially introducing higher wavenumber details into the model. We show that the TTT allows overcoming the issues associated with the nonlinearity intrinsic to FWI. We also disentangle envelope and phase from the waveform to choose the objective function most suitable for FWI. We assess the accuracy of initial models and predict the quality of the FWI results by quantifying the early arrival cycle skipping between original and simulated data. The efficiency of the workflow is tested with a challenging synthetic target model, containing vertical boundaries with strong velocity contrasts and velocity inversions embedded in a checkerboard-like pattern. We show that workflow steps 1) and 2) provide a TTT model that is not cycle skipped at the frequencies available in most marine seismic experiments and thus allow step 3) FWI to obtain high-resolution VP models of the subsurface using band- and offset-limited field datasets, traditionally collected in marine airgun and streamer acquisitions This work has been done in the framework of project FRAME (Reference CTM2015-71766-R) and project ATLANTIS PID2019-109559RB-I00, funded by the Spanish Ministry of Research and Innovation and has also had the funding support of the Severo Ochoa Centre of Excellence accreditation (CEX2019-000928-S), of the Spanish Research Agency (Agencia Española de Investigación, AEI) |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|