Velocity and interface depth determination by tomography of depth migrated gathers
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- Dan Kosloff
- Department of Geophysics, Tel Aviv University, Tel Aviv, Israel 69978 and Paradigm Geophysical Ltd., Beit Merkazim, P.O. Box 2061, Herzlia, Israel
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- John Sherwood
- Geophysical Development Corporation, 8401 Westheimer, Suite 150, Houston, TX 77063
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- Zvi Koren
- Paradigm Geophysical Ltd., Beit Merkazim, P.O. Box 2061, Herzlia, Israel
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- Elana Machet
- Paradigm Geophysical Ltd., Beit Merkazim, P.O. Box 2061, Herzlia, Israel
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- Yael Falkovitz
- Paradigm Geophysical Ltd., Beit Merkazim, P.O. Box 2061, Herzlia, Israel
説明
<jats:p> A method for velocity and interface depth determination based on tomography of migrated common reflecting point (CRP) gathers is presented. The method is derived from the tomographic principle that relates traveltime change along a given ray to perturbations in slowness and layer depths. The tomographic principle is used to convert depth errors in migrated CRP gathers to time errors along a CRP ray pair and thus enable use of conventional traveltime tomography. It is also used to affect a very fast prestack migration and set up the tomography matrix. The velocity‐depth determination method uses the available offsets of all CRPs and inverts for the parameters of all layers simultaneously. Hand picking of depth errors on CRP gathers is avoided by a method where the tomography matrix operates directly on the migrated gathers. The velocity‐depth determination method is demonstrated on a synthetic example and on a field example from the North Sea. </jats:p>
収録刊行物
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- GEOPHYSICS
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GEOPHYSICS 61 (5), 1511-1523, 1996-09
Society of Exploration Geophysicists
