| Autor: |
Matthieu Bulteau, R. Smith, Gilles Lambaré, Patrice Guillaume, Jalila Riyami, Art McCarthy, Jean-Philippe Montel, P. Zwartjes |
| Rok vydání: |
2010 |
| Předmět: |
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| Zdroj: |
SEG Technical Program Expanded Abstracts 2010. |
| DOI: |
10.1190/1.3513793 |
| Popis: |
A step change has been made in seismic imaging when moving from narrow-azimuth (NAZ) imaging to wide-azimuth (WAZ) imaging, mainly because of better illumination and higher fold. Likewise, a wider angular redundancy should help building more realistic depth velocity models as long as involved picking and tomography engines can correctly handle the geometry of wideazimuth surveys. For that purpose, the seismic dataset is split into common offset vector (COV) volumes gathering traces having a homogeneous offset and azimuth distribution and insuring minimum holes or fold variations due to acquisition irregularities (Vermeer, 2002). We present a non-linear slope tomography that has been extended to invert locally coherent events picked in prestack depth migrated (PreSDM) or prestack time migrated (PreSTM) COVs. We address picking and de-migration aspects as well as kinematic re-migration and velocity update processes. We illustrate our COV consistent model building workflow on a real high-density WAZ survey from the Sultanate of Oman. We show how velocity model and imaging have been improved when picking is done on gathers built from COVs rather than on gathers built from azimuth sectors. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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