Depth filtering for one‐component seismic data

Geophysics ◽  
1991 ◽  
Vol 56 (9) ◽  
pp. 1482-1485 ◽  
Author(s):  
Robert Sun ◽  
George A. McMechan
Keyword(s):  
Seismic Data ◽  
Seismic Waves ◽  
Downward Continuation ◽  
Near Surface ◽  
Left Behind ◽  
Elastic Data ◽  
Ground Roll ◽  
The Waves ◽  
Seismic Wavefield ◽  
Number Of Authors

The concept of downward continuation of a seismic wavefield recorded on the earth’s surface to remove near‐surface effects has previously been applied by a number of authors including Schultz and Sherwood (1980), Berryhill (1979, 1984), and McMechan and Chen (1990). Recently, McMechan and Sun (1991) demonstrated, using synthetic elastic data, that downward continuation of an elastic (two‐component) seismic wavefield separates various seismic waves, based on their depth of propagation. This was used to simultaneously remove direct waves and ground roll. The direct compressional and shear waves and the ground roll get left behind in the near surface during downward continuation; subsequent upward continuation reconstructs the surface‐recorded wavefield without the waves propagating in the shallow layers.

Depth filtering of first breaks and ground roll

Geophysics ◽  
1991 ◽  
Vol 56 (3) ◽  
pp. 390-396 ◽  
Author(s):  
G. A. McMechan ◽  
R. Sun
Keyword(s):  
Traveling Waves ◽  
Velocity Model ◽  
Common Source ◽  
Reverse Time ◽  
Near Surface ◽  
Compressional Waves ◽  
Left Behind ◽  
Ground Roll ◽  
Wavefield Extrapolation ◽  
Time Extrapolation

Much of the energy removed in a typical standard seismic data preprocessing sequence corresponds to approximately horizontal propagation in very near‐surface structure. Such energy includes direct (first‐break) compressional waves, direct shear waves, and ground roll; these may be effectively separated from deeper reflections by downward continuation of the recorded common‐source wavefield, by reverse‐time extrapolation, to a depth beneath which these waves propagate. The subhorizontally traveling waves get left behind in the shallow part of the model. Subsequent upward continuation of the wavefield reconstructs the original surface‐recorded wavefield with the subhorizontally traveling waves removed. Only a very simple (even constant) velocity distribution is required for the wavefield extrapolation; no net distortion is produced since both downward and upward continuations are performed using the same velocity model.

scholarly journals Interferometric ground-roll removal: Attenuation of scattered surface waves in single-sensor data

Geophysics ◽  
2010 ◽  
Vol 75 (2) ◽  
pp. SA15-SA25 ◽  
Author(s):  
David F. Halliday ◽  
Andrew Curtis ◽  
Peter Vermeer ◽  
Claudio Strobbia ◽  
Anna Glushchenko ◽  
...  
Keyword(s):  
Surface Wave ◽  
Surface Waves ◽  
Seismic Data ◽  
Sensor Data ◽  
Seismic Survey ◽  
Seismic Interferometry ◽  
Near Surface ◽  
Reflection Data ◽  
Ground Roll ◽  
Single Sensor

Land seismic data are contaminated by surface waves (or ground roll). These surface waves are a form of source-generated noise and can be strongly scattered by near-surface heterogeneities. The resulting scattered ground roll can be particularly difficult to separate from the desired reflection data, especially when this scattered ground roll propagates in the crossline direction. We have used seismic interferometry to estimate scattered surface waves, recorded during an exploration seismic survey, between pairs of receiver locations. Where sources and receivers coincide, these interreceiver surface-wave estimates were adaptively subtracted from the data. This predictive-subtraction process can successfully attenuate scattered surface waves while preserving the valuable reflected arrivals, forming a new method of scattered ground-roll attenuation. We refer to this as interferometric ground-roll removal.

Near-surface scattered waves enhancement with source-receiver interferometry

Geophysics ◽  
2018 ◽  
Vol 83 (6) ◽  
pp. Q49-Q69
Author(s):  
Jixiang Xu ◽  
Shitai Dong ◽  
Huajuan Cui ◽  
Yan Zhang ◽  
Ying Hu ◽  
...  
Keyword(s):  
Seismic Data ◽  
Seismic Waves ◽  
Scattered Wave ◽  
Receiver Functions ◽  
Surface Velocity ◽  
Seismic Exploration ◽  
Common Source ◽  
Constructive Interference ◽  
Near Surface ◽  
The Common

Near-surface scattered waves (NSWs) are the main noise in seismic data in areas with a complex near surface and can be divided into surface-to-surface scattered waves and body-to-surface scattered waves. We have developed a method for NSW enhancement that uses modified source-receiver interferometry. The method consists of two parts. First, deconvolutional intersource interferometry is used to cancel the common raypath of seismic waves from a near-surface scatterer to the common receiver and the receiver function. Second, convolutional interreceiver interferometry is used to compensate the common raypath of seismic waves from the common source to the near-surface scatterer and the source function. For an isotropic point scatterer near the earth’s surface in modified source-receiver interferometry, a body-to-surface scattered wave can be reconstructed by constructive interference not only among three body-to-surface scattered waves but also among a body-to-surface scattered wave and two surface-to-surface scattered waves; a surface-to-surface scattered wave can be reconstructed by constructive interference not only among three surface-to-surface scattered waves but also among a surface-to-surface scattered wave and two body-to-surface scattered waves. According to stationary phase analysis based on the superposition principle, we have developed a so-called dual-wheel driving configuration of modified source-receiver interferometry for enhancing NSWs in the data of conventional seismic exploration. The main advantages of the scheme are that (1) it can be used to enhance NSWs without the need for any a priori knowledge of topography and near-surface velocity, (2) it can be used to reconstruct NSWs from real sources to real receivers, including 3D near-surface side-scattered waves, and (3) it can be applied to conventional seismic data with finite-frequency bandwidth, spatially limited and sparse arrays, different source and receiver functions, and static correction. Numerically simulated data and field seismic data are used to demonstrate the feasibility and effectiveness of the scheme.

APPLICATION OF THE EMPIRICAL MODE DECOMPOSITION METHOD TO GROUND-ROLL NOISE ATTENUATION IN SEISMIC DATA

2013 ◽  
Vol 31 (4) ◽  
pp. 619 ◽  
Author(s):  
Luiz Eduardo Soares Ferreira ◽  
Milton José Porsani ◽  
Michelângelo G. Da Silva ◽  
Giovani Lopes Vasconcelos
Keyword(s):  
Empirical Mode Decomposition ◽  
Seismic Data ◽  
Low Frequency ◽  
High Amplitude ◽  
Seismic Line ◽  
Seismic Processing ◽  
Mode Decomposition ◽  
Ground Roll ◽  
Fortran 90 ◽  
Emd Method

ABSTRACT. Seismic processing aims to provide an adequate image of the subsurface geology. During seismic processing, the filtering of signals considered noise is of utmost importance. Among these signals is the surface rolling noise, better known as ground-roll. Ground-roll occurs mainly in land seismic data, masking reflections, and this roll has the following main features: high amplitude, low frequency and low speed. The attenuation of this noise is generally performed through so-called conventional methods using 1-D or 2-D frequency filters in the fk domain. This study uses the empirical mode decomposition (EMD) method for ground-roll attenuation. The EMD method was implemented in the programming language FORTRAN 90 and applied in the time and frequency domains. The application of this method to the processing of land seismic line 204-RL-247 in Tacutu Basin resulted in stacked seismic sections that were of similar or sometimes better quality compared with those obtained using the fk and high-pass filtering methods.Keywords: seismic processing, empirical mode decomposition, seismic data filtering, ground-roll. RESUMO. O processamento sísmico tem como principal objetivo fornecer uma imagem adequada da geologia da subsuperfície. Nas etapas do processamento sísmico a filtragem de sinais considerados como ruídos é de fundamental importância. Dentre esses ruídos encontramos o ruído de rolamento superficial, mais conhecido como ground-roll . O ground-roll ocorre principalmente em dados sísmicos terrestres, mascarando as reflexões e possui como principais características: alta amplitude, baixa frequência e baixa velocidade. A atenuação desse ruído é geralmente realizada através de métodos de filtragem ditos convencionais, que utilizam filtros de frequência 1D ou filtro 2D no domínio fk. Este trabalho utiliza o método de Decomposição em Modos Empíricos (DME) para a atenuação do ground-roll. O método DME foi implementado em linguagem de programação FORTRAN 90, e foi aplicado no domínio do tempo e da frequência. Sua aplicação no processamento da linha sísmica terrestre 204-RL-247 da Bacia do Tacutu gerou como resultados, seções sísmicas empilhadas de qualidade semelhante e por vezes melhor, quando comparadas as obtidas com os métodos de filtragem fk e passa-alta.Palavras-chave: processamento sísmico, decomposição em modos empíricos, filtragem dados sísmicos, atenuação do ground-roll.

Regularization and datuming of seismic data by weighted, damped least squares

Geophysics ◽  
2006 ◽  
Vol 71 (5) ◽  
pp. U67-U76 ◽  
Author(s):  
Robert J. Ferguson
Keyword(s):  
Least Squares ◽  
Seismic Data ◽  
Synthetic Data ◽  
Real Data ◽  
Structural Data ◽  
Irregular Sampling ◽  
Data Set ◽  
Near Surface ◽  
Damped Least Squares ◽  
Wavefield Extrapolation

The possibility of improving regularization/datuming of seismic data is investigated by treating wavefield extrapolation as an inversion problem. Weighted, damped least squares is then used to produce the regularized/datumed wavefield. Regularization/datuming is extremely costly because of computing the Hessian, so an efficient approximation is introduced. Approximation is achieved by computing a limited number of diagonals in the operators involved. Real and synthetic data examples demonstrate the utility of this approach. For synthetic data, regularization/datuming is demonstrated for large extrapolation distances using a highly irregular recording array. Without approximation, regularization/datuming returns a regularized wavefield with reduced operator artifacts when compared to a nonregularizing method such as generalized phase shift plus interpolation (PSPI). Approximate regularization/datuming returns a regularized wavefield for approximately two orders of magnitude less in cost; but it is dip limited, though in a controllable way, compared to the full method. The Foothills structural data set, a freely available data set from the Rocky Mountains of Canada, demonstrates application to real data. The data have highly irregular sampling along the shot coordinate, and they suffer from significant near-surface effects. Approximate regularization/datuming returns common receiver data that are superior in appearance compared to conventional datuming.

DISPERSION IN SEISMIC SURFACE WAVES

Geophysics ◽  
1951 ◽  
Vol 16 (1) ◽  
pp. 63-80 ◽  
Author(s):  
Milton B. Dobrin
Keyword(s):  
Surface Waves ◽  
Water Waves ◽  
Seismic Refraction ◽  
Wave Theory ◽  
Wave Dispersion ◽  
Surface Zone ◽  
Surface Wave Dispersion ◽  
Near Surface ◽  
Arrival Times ◽  
Ground Roll

A non‐mathematical summary is presented of the published theories and observations on dispersion, i.e., variation of velocity with frequency, in surface waves from earthquakes and in waterborne waves from shallow‐water explosions. Two further instances are cited in which dispersion theory has been used in analyzing seismic data. In the seismic refraction survey of Bikini Atoll, information on the first 400 feet of sediments below the lagoon bottom could not be obtained from ground wave first arrival times because shot‐detector distances were too great. Dispersion in the water waves, however, gave data on speed variations in the bottom sediments which made possible inferences on the recent geological history of the atoll. Recent systematic observations on ground roll from explosions in shot holes have shown dispersion in the surface waves which is similar in many ways to that observed in Rayleigh waves from distant earthquakes. Classical wave theory attributes Rayleigh wave dispersion to the modification of the waves by a surface layer. In the case of earthquakes, this layer is the earth’s crust. In the case of waves from shot‐holes, it is the low‐speed weathered zone. A comparison of observed ground roll dispersion with theory shows qualitative agreement, but it brings out discrepancies attributable to the fact that neither the theory for liquids nor for conventional solids applies exactly to unconsolidated near‐surface rocks. Additional experimental and theoretical study of this type of surface wave dispersion may provide useful information on the properties of the surface zone and add to our knowledge of the mechanism by which ground roll is generated in seismic shooting.

Passive near-surface seismic data where all else fails

2013 ◽  
Vol 32 (3) ◽  
pp. 308-314
Author(s):  
Phil Sirles ◽  
Jacob Sheehan ◽  
Nicole Pendrigh
Keyword(s):  
Seismic Data ◽  
Near Surface
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