Wavefront construction modeling and inversion of VSP data for anisotropy parameters

2003 ◽  
Author(s):  
Richard L. Gibson ◽  
Vincent Durussel ◽  
Kyoung‐Jin Lee
Keyword(s):  
Vsp Data ◽  
Anisotropy Parameters ◽  
And Inversion

On full-waveform modeling and inversion of fiber-optic VSP data

2017 ◽  
Author(s):  
Olga Podgornova ◽  
Scott Leaney ◽  
Smaine Zeroug ◽  
Lin Liang
Keyword(s):  
Fiber Optic ◽  
Waveform Modeling ◽  
Full Waveform ◽  
Vsp Data ◽  
And Inversion

Estimating anisotropy parameters and traveltimes in the τ‐p domain

Geophysics ◽  
2002 ◽  
Vol 67 (4) ◽  
pp. 1076-1086 ◽  
Author(s):  
Mirko van der Baan ◽  
J. Michael Kendall
Keyword(s):  
Anisotropic Media ◽  
Seismic Wave Propagation ◽  
Linear Process ◽  
Fast Method ◽  
Forward Modelling ◽  
Interval Estimates ◽  
Taylor Series Expansions ◽  
Local Interval ◽  
Anisotropy Parameters ◽  
And Inversion

The presence of anisotropy influences many aspects of seismic wave propagation and has therefore implications for conventional processing schemes. To estimate the anisotropy, we need both forward modelling and inversion tools. Exact forward modelling in anisotropic media is generally done by raytracing. However, we present a new and fast method, using the τ‐p transform, to calculate exact P and SV reflection moveout curves in stratified, laterally homogeneous, anisotropic media which requires no ray tracing. Results are exact even if the SV‐waves display cusps. In addition, we show how the same method can be used for parameter estimation. Since inversion for anisotropic parameters is very nonunique, we develop expressions requiring only a reduced number of parameters. Nevertheless, predictions using these expressions are more accurate than Taylor series expansions and are also able to handle cusps in the SV traveltime curves. In addition, layer stripping is a linear process. Therefore, both effective (average) and local (interval) estimates can be obtained.

Multiparameter TTI tomography of P-wave reflection and VSP data

Geophysics ◽  
2013 ◽  
Vol 78 (5) ◽  
pp. WC51-WC63 ◽  
Author(s):  
Xiaoxiang Wang ◽  
Ilya Tsvankin
Keyword(s):  
Symmetry Axis ◽  
Model Updating ◽  
Transversely Isotropic ◽  
P Wave ◽  
Ocean Bottom ◽  
Symmetry Direction ◽  
Direction Parallel ◽  
The North ◽  
Vsp Data ◽  
Anisotropy Parameters

Transversely isotropic models with a tilted symmetry axis (TTI media) are widely used in depth imaging of complex geologic structures. Here, we present a modification of a previously developed 2D P-wave tomographic algorithm for estimating heterogeneous TTI velocity fields and apply it to synthetic and field data. The symmetry-direction velocity [Formula: see text], anisotropy parameters [Formula: see text] and [Formula: see text], and symmetry-axis tilt [Formula: see text] are defined on a rectangular grid. To ensure stable reconstruction of the TTI parameters, reflection data are combined with walkaway vertical seismic profiling (VSP) traveltimes in joint tomographic inversion. To improve the convergence of the algorithm, we develop a three-stage model-updating procedure that gradually relaxes the constraints on the spatial variations of the anisotropy parameters, while the symmetry axis is kept orthogonal to the reflectors. Only at the final stage of the inversion are the parameters [Formula: see text], [Formula: see text], and [Formula: see text] updated on the same grid. We also incorporate geologic constraints into tomography by designing regularization terms that penalize parameter variations in the direction parallel to the interfaces. First, we examine the performance of the regularized joint tomography of reflection and VSP data for two sections of the BP TTI model that contain an anticline and a salt dome. All three TTI parameters in the shallow part of both sections (down to 5 km) are well resolved by the proposed model-updating process. Then, the algorithm is applied to a 2D section from 3D ocean-bottom seismic data acquired at Volve field in the North Sea. The inverted TTI model produces well-focused reflectors throughout the section and accurately positions the key horizons, which is confirmed by the available well markers.

Borehole-Driven 3D Surface Seismic Data Processing Using DAS-VSP Data

2021 ◽  
Author(s):  
Gang Yu ◽  
Junjun Wu ◽  
Yuanzhong Chen ◽  
Ximing Wang
Keyword(s):  
Data Processing ◽  
Data Acquisition ◽  
Seismic Data ◽  
Field Data ◽  
Seismic Data Processing ◽  
3D Surface ◽  
Data Volume ◽  
Vsp Data ◽  
Seismic Data Acquisition ◽  
Anisotropy Parameters

Abstract A 3D surface seismic data acquisition project was conducted simultaneously with 3D DAS-VSP data acquisition in one well in Jilin Oilfield of Northen China. The 3D surface seismic data acquisition project covered an area of 75 km2, and one borehole (DS32-3) and an armoured optical cable with high temperature single mode fiber were used to acquire the 3D DAS-VSP data simultaneously when the crew was acquiring the 3D surface seismic data. The simultaneously acquired 3D DAS-VSP data were used to extract formation velocity, deconvolution operator, absorption, attenuation (Q value), anisotropy parameters (η, δ, ε) as wel as enhanced the surface seismic data processing including velocity model calibration and modification, static correction, deconvolution, demultiple processing, high frequency restoration, anisotropic migration, and Q-compensation or Q-migration. In this project, anisotropic migration, Q-migration was conducted with the anisotropy parameters (η, δ, ε) data volume and enhanced Q-field data volume obtained from the joint inversion of both the near surface 3D Q-field data volume from uphole data and the mid-deep layer Q-field data volume from all available VSP data in the 3D surface seismic surveey area. The anosotropic migration and Q-migration results show much sharper and focussed faults and and clearer subsutface structure.

Slowness surface construction and inversion from 3D VSP data

First Break ◽  
2011 ◽  
Vol 29 (1768) ◽  
Author(s):  
J.C. Owusu ◽  
S.A. Horne ◽  
A. Shabbir
Keyword(s):  
Slowness Surface ◽  
Vsp Data ◽  
And Inversion ◽  
Surface Construction

scholarly journals P-Wave-Only Inversion of Challenging Walkaway VSP Data for Detailed Estimation of Local Anisotropy and Reservoir Parameters: A Case Study of Seismic Processing in Northern Poland

Energies ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2061
Author(s):  
Mateusz Zaręba ◽  
Tomasz Danek ◽  
Michał Stefaniuk
Keyword(s):  
Seismic Signal ◽  
Field Conditions ◽  
P Wave ◽  
Quality Data ◽  
Local Anisotropy ◽  
Processing Scheme ◽  
Vsp Data ◽  
Walkaway Vsp ◽  
Anisotropy Parameters ◽  
Detailed Interpretation

In this paper, we present a detailed analysis of walkaway vertical seismic profiling (VSP) data, which can be used to obtain Thomsen parameters using P-wave-only inversion. Data acquisition took place in difficult field conditions, which influenced the quality of the data. Therefore, this paper also shows a seismic data processing scheme that allows the estimation of correct polarization angles despite poor input data quality. Moreover, we showed that it is possible to obtain reliable and detailed values of Thomsen’s anisotropy parameters for data that are challenging due to extremely difficult field conditions during acquisition and the presence of an overburden of salt and anhydrite (Zechstein formation). This complex is known for its strong seismic signal-attenuating properties. We designed a special processing workflow with a signal-matching procedure that allows reliable estimation of polarization angles for low-quality data. Additionally, we showed that P-wave-only inversion for the estimation of local anisotropy parameters can be used as valuable additional input for detailed interpretation of geological media, even if anisotropy is relatively low.

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