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Raypath parameter/es

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Proceedings Papers

Paper presented at the 1998 SEG Annual Meeting, September 13–18, 1998
Paper Number: SEG-1998-1859
... array, and recursiv e interpolation is used to nd the desired rays. These rays may then be used as paths for the computation of F rechet deriv ativ es. F rec het derivativ es of trav eltime and raypath In order to solv e the inverse problem, it is necessary to deriv e expressions for the partial deriv...
Proceedings Papers

Paper presented at the 1989 SEG Annual Meeting, October 29–November 2, 1989
Paper Number: SEG-1989-0922
..., as a linear function of slowness (reciprocal velocity) perturbations along the reflected raypaths. They inverted the combined linear op- erators by iterative least-squares methods to estimate local velocity anomalies from the picked stacking parameters. To avoid an unweildy operator, they assumed straight...
Proceedings Papers

Paper presented at the 1993 SEG Annual Meeting, September 26–30, 1993
Paper Number: SEG-1993-0888
... ABSTRACT No preview is available for this paper. amplitude calculate traveltime colorado school smooth velocity function upstream oil & gas traveltime raypath velocity model wave phenomenon reservoir characterization interpolation algorithm seismic modeling equation...
Proceedings Papers

Paper presented at the 1986 SEG Annual Meeting, November 2–6, 1986
Paper Number: SEG-1986-0577
... with addi- tional (a priori) information or a large amount of data involving independent paths in the medium. Offset or walkaway VSPs combine the advantages of large raypath coverage and good es- timates for the interface locations and velocities at the well, es- pecially when logs or near offset VSPs...
Journal Articles
Petrophysics 60 (02): 335–347.
Paper Number: SPWLA-2019-v60n2a10
Published: 01 April 2019
... the filtered waveform measurements, an automated time pick and event-localization procedure is used to collect possible reflected arrival events. An automated ray-tracing and 3D slowness time coherence (STC) procedure is used to determine the raypath type of the arrival event and the reflector azimuth...
Proceedings Papers

Paper presented at the 6th ISRM Congress, August 30–September 3, 1987
Paper Number: ISRM-6CONGRESS-1987-123
... rekonstruiert werden. Die Leistung des Rekonstruktionsalgorithmus wurde unter Verwendung von Daten kuenstlicher Modelle untersucht. Es wurde dann auf seismische Felddaten, die wahrend der Untersuchung in Tunneln an der Dammseite ermittelt worden waren, angewendet und mit den abgeleiteten geotechnischen Daten...
Proceedings Papers

Paper presented at the 1992 SEG Annual Meeting, October 25–29, 1992
Paper Number: SEG-1992-0979
...: VC(Z) = v, t kr, (1) where V, is the vertical velocity at the surface z = 0. Figure 2 illustrates the two-phase search procedure we use in ray tracing between a specified source and receiver location. Once the raypath and its ray parameter are determined, numerical integration is still required...
Proceedings Papers

Paper presented at the 1998 SEG Annual Meeting, September 13–18, 1998
Paper Number: SEG-1998-1720
... an alternativ e to cell parameterization so as to reduce the number of parameters to a minimum. Y et, it allows a certain exibilit yto accommodate complex structures. I constructed 2-D anomalies based on 1-D functions. Es- sentially, the anomaly is represen ted by tw o separate parts: (1) a at region of width...
Proceedings Papers

Paper presented at the 1987 SEG Annual Meeting, October 11–15, 1987
Paper Number: SEG-1987-0262
... informations such as first layer thicknesses and refractor velocities, using the first arrivals on seismic records. The infor- mations derived can be used to estimate initial static corrections. In this method, refraction raypaths are modelled as the sum of three segments: the downgoing and the upcoming...
Proceedings Papers

Paper presented at the 1999 SEG Annual Meeting, October 31–November 5, 1999
Paper Number: SEG-1999-1715
... domain. A combination of the forw ardand inverse operators with a di eren- tial operator in the scattering-angle/azimuth domain giv es the sensitivit y transform. Applying this trans- form to the data after the inversion/migration, can giv e an estimate of how good the current bac kground model is based...
Proceedings Papers

Paper presented at the 1986 SEG Annual Meeting, November 2–6, 1986
Paper Number: SEG-1986-0572
... position A and D are shown together with the raypath coverage diagram. The ob- FIG. 1. Seismic section of line ES-I. Seismic 14 573 FIG. 2. Modeling examples for offset VSP surveys. (a) Syn- thetic upgoing events for offset D, (b) synthetic upgoing events for offset A, (c) synthetic model and raypath...
Proceedings Papers

Paper presented at the 2011 SEG Annual Meeting, September 18–23, 2011
Paper Number: SEG-2011-0237
... and subsalt plays are often achieved by employing transversely isotropic models with a vertical (VTI) or tilted (TTI) symmetry axis (Behera and Tsvankin, 2009; Neal et al., 2009; Bakulin et al., 2010a). To ensure stable es- timation of the symmetry-direction P-wave velocity VP0 and anisotropy parameters...
Proceedings Papers

Paper presented at the 2000 SEG Annual Meeting, August 6–11, 2000
Paper Number: SEG-2000-2281
... Summary This paper considers traveltimes related to oblique ray trajectories under the assumption of linear velocity as a function of depth. Exact traveltime expressions for oblique raypaths are used for a rigorous nonlinear regression analysis of zero and offset Vertical Seismic Profile (VSP...
Proceedings Papers

Paper presented at the 2013 SEG Annual Meeting, September 22–27, 2013
Paper Number: SEG-2013-1324
... Summary An analysis of walkaway and multi-offset VSP shows that reflection data in the multi-offset VSP can extend vertical-angle range covered by the direct arrivals and provide additional constraints to the estimated anisotropic parameters. Because raypaths in the reflection data are longer...
Proceedings Papers

Paper presented at the Safety in Offshore Engineering: Proceedings of an international conference, April 25–26, 1990
Paper Number: SUT-AUTOE-v25-193
... reversal, recognlslng d ~ f t r a c t ~ o n s and t rack~ng weak events S e n s ~ t ~ v e parameter for ~ d e n t ~ t y ~ n g veloc~ty anomal~es Sens~t lve parameter ~ n d ~ c a t ~ v e of lateral veloc~ty var~at lons As above plus absorp t~on of energy from raypaths passing through a gas sand...
Proceedings Papers

Paper presented at the 1984 SEG Annual Meeting, December 2–6, 1984
Paper Number: SEG-1984-0370
... an inversion procedure based on parameter estimation. Compared with forward modeling it has two main advantages. First. il is efficient: second, it is pohsihle to carry out a detailed re>olution analysis to as$es\ the resolving power of the available data for the model par;mctcr\. Such an analysi\ is of great...
Proceedings Papers

Paper presented at the 2000 SEG Annual Meeting, August 6–11, 2000
Paper Number: SEG-2000-2138
.... In the standard method, traveltimes are picked, and the di erences be- tween the observed and calculated traveltimes are then smeared along the corresponding rays to update the ve- locity model. t t cal t obs= - T11 T12 T22 T23 T33 T31= - + - + - t12 t31 t23 t obs = + + Smeared along 6 raypaths Data: tij Tij...
Proceedings Papers

Paper presented at the 2016 SEG International Exposition and Annual Meeting, October 16–21, 2016
Paper Number: SEG-2016-13951595
... ABSTRACT Subsalt velocity model building is challenging due to a limited seismic raypath, narrow angle coverage, scattering effects, and mode conversion caused by the large elastic property contrast between the salt body and background sediments. Uncertainty in the salt geometry and lack...
Proceedings Papers

Paper presented at the 2009 SEG Annual Meeting, October 25–30, 2009
Paper Number: SEG-2009-2491
...), Chakraborty et al. (1998) and others. They explained how seismic velocities can be estimated along raypaths between boreholes and demonstrated their results with real field examples. Imaging techniques used in these applications include back projection (Dynes and Lytle, 1979), back propagation (Witten...
Proceedings Papers

Paper presented at the 2004 SEG Annual Meeting, October 10–15, 2004
Paper Number: SEG-2004-0139
... along the raypath. The relationship between the group and phase (plane-wave) attenuation coefficients involves just the group and phase angles and can be used to estimate the Thomsen-style parameters from wide-angle attenuation measurements. attenuative ti media velocity anisotropy anisotropy...

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