Filtering filtering is used in seismic data processing to enhance the signal quality by suppressing undesirable acquisition or processing noise or artifacts which can alter seismic data i. However, the high computational cost of generating 3d synthetic data, followed by the process of migration, limits the number of scenarios that can be validated. It can be concluded that the gps combination is a little better than the glonass combination, the reason may be that the pseudorange observation of the glonass with a larger noise than gps tu et al. Seismic inverse q filtering yanghua wang download here seismic inverse q filtering is a data processing technology for enhancing the resolution of seismic images. In this paper, seismic inverse qfiltering is implemented in a stabilized manner to produce.
This results in frequencydependent seismic attenuation reduced amplitude of higher frequencies with travel time and dispersion a phase change in the embedded wavelet. It has different polarization properties than those of p and s waves. Enhanced downhole microseismic processing using matched. Generalized stable inverse q filtering sciencedirect. This page contains list of freely available ebooks, online textbooks and tutorials in geophysics. Us7366054b1 taup filters for removal of noise from. Microseismic events enhancement in sensor arrays using. For seismic reflection data, the coupling between seismic wavelets and the reflectivity sequences hinders their usage for q. A stable and selfadaptive approach for inverse qfilter. Abstract our primary investigative tool for understanding the subsurface prospectivity is seismic data, where energy reflected from different seismic horizons can reveal the physical properties of these. Seismic migration with inverse q filtering wang 2004. Q filter dug insight user manual downunder geosolutions. It employs a wave propagation reversal procedure that compensates for energy absorption and corrects wavelet distortion due to velocity dispersion.
Simultaneous inversion of multiple microseismic data for event locations and velocity model with bayesian inference zhishuai zhang 1, james w. Robinson pointed out that the algorithm of inverse q filtering is similar to seismic deconvolution. I would like to begin by first thanking all of those at the founding member universities for all the. Here,wefirstgiveanoverviewof crazyseismic, followed by a summary of its core functionalities.
Seismic inverse q filtering can be regarded as a reversal procedure of wave propagation. Seismic migration with inverse q filtering, geophysical. It has been an exciting and busy first year, and we have a lot of information we want to share. This filtering step in seismic processing can be critical in budget. Ideally, the process of inverse q filtering improves the. Cmp processing greatly enhances the signal to noise ratio. Network connectivity will help processing analysts working from remote places, be it home or on tour. Realtime coseismic wave retrieving by integrated kalman. Threedimensional sparse seismic deconvolution based on. Pdf stability and efficiency are two issues of general concern in inverse q filtering. Probabilistic foundation of inverse theory albert tarantola pdf. Q factor estimation from the amplitude spectrum of the.
Estimation of q factors from reflection seismic data for a. To obtain a solution when we make computations with a seismic. By clicking the download button, you will be required to provide a valid work email address. Download fulltext pdf anseismic a simple assistant computer program for implementing earthquake analysis of structures with ansys and sap2000 conference paper pdf available september. Check our section of free ebooks and guides on geophysics now. Pdf anseismic a simple assistant computer program for.
Seismic inverse q filtering is a data processing technology for enhancing the resolution of reflection seismology images. Contents preface viii 1 introduction to inverse q filtering 1 1. In the datanoisefree case here, the background noise is the numerical errors. Cmp processing greatly enhances the signal to noise ratio and allows coherent reflections to be visible. The main factor affecting converted wave resolution is the absorption of seismic. An inverse qfilter algorithm based on stable wavefield continuation. An inverse qfilter algorithm based on stable wavefield. Characterization of seismic attenuation, quantified by q, is desirable for seismic processing and interpretation.
The q filter applies or removes corrections for dispersion and attenuation. Inverse q filtering is then carried out, removing the timevariant wavelet effects by absorption and broadening the effective seismic bandwidth by correcting the loss of highfrequency signal as well as compensating for dispersion effects that rotate each spectral component by a different amount. Simultaneous inversion of multiple microseismic data for. The interval q model can be used to design the inverse q filter, alternatively, we use the reliable average q model to determine the inverse q filter. When seismic waves propagate through the earth subsurface, the anelasticity and. For periods up to 300 s, the vertical displacement corresponds to rayleigh waves generated like the primary microseisms, with the difference that it involves the. Inverse q filter for seismic resolution enhancement seg library. Buy seismic inverse q filtering book online buy seismic inverse q filtering book online at best prices in india on. Microseismic events enhancement in sensor arrays using autocorrelation based filtering e. In this paper we present a stable approach to inverse q filtering, based on the theory of wavefield downward continuation. Q is the anelastic attenuation factor or the seismic quality factor, a measure of the energy loss as the seismic wave moves. Extracting meaningful information from seismic attributes cseg. This collection of articles has been authored by microseismic employees and is available free of charge. We then conduct a test using real data to verify the result of inverse q filtering of a seismic section using a time varying q factor function derived from the proposed method.
Nava abstract we have applied bayesian inference for simultaneous inversion of multiple microseismic data to obtain event locations along with the subsurface velocity model. The cdp 88 seismic trace before inverse q filtering is marked by 1. System requirements video card requirements download and installing on. By compensating for amplitude attenuation with a model of the viscoelastic attenuation model type, seismic. We launched ucfer a year ago and would like to update everyone on our progress. By compensating for amplitude attenuation, seismic. Products global seismic solutions gss is an australasia based company that specialises in providing specialist seismic explosive products and services to the global oil, gas and coal exploration industries. Baseline assessment of seismic hazards in british columbias. The inverse q filter procedure attempts to eliminate the effect of the earth q filter and hence improve the seismic resolution. Note in particular that the ai is much cleaner, and retains good structural conformance. Quantifying the effectiveness of stabilized inverse q. Highresolution seismic processing by gabor deconvolution.
The numerical instability of inverse q filter amplitude compensation reduces the. Inverse qfilter for seismic resolution enhancement spiral. Walter lynn this course is designed for those working with reflection seismic data to. For example, w 3 is a filtering window with size 3. The energy dissi pation and velocity dispersion of the seismic wave require suitable. A slight, but detectable, incessant excitation of the earths free oscillations, or normal modes, with periods in the range 30 to s, and is often referred to as the earth hum. The interval q values obtained from such a q analysis procedure are listed as follows. Modified kolsky model for seismic attenuation and dispersion.
However, the data that goes into the cmp processing is often contaminated with noise. Seismic inverse q filtering is a data processing technology for enhancing the. Sacchi and tadeusz 1995 proposed an improved algorithm for the parabolic radon transform to get higher resolution. Inverse q filtering in 3d pp and psv seismic data a. Pdf inverse qfilter for seismic resolution enhancement. Pdf inverse q filtering via synchrosqueezed wavelet. Seismic imaging of subsurface geology training course. Seismic inverse q filtering is a data processing technology for enhancing the resolution of. The stable approach of inverse q filtering based on wavefield.
To solve this problem, we propose an approach of inverse q filtering. The improvement of converted wave resolution is one of the key problems. Planning for a hpc seismic data processing facility. The stable approach of inverse q filtering based on wavefield continuation theory can simultaneously perform amplitude compensation and phase correction. By compensating for amplitude attenuation, seismic data can provide true. Seismic inverse q filtering this book is dedicated to my wife guoling, and my two children brian and claire. Pdf a stable and efficient approach of inverse q filtering. Once attenuation is measured, it is possible to mitigate the resolution loss by applying processes such as inverse q filtering to raise the highfrequency content of later times in seismic sections to compensate for attenuation of the seismic. Ground roll is an elliptically polarized wave with retrograde particle motion. Stabilized inverse q filtering wang 2002 developed a stabilized algorithm for inverse q. Electromagnetics, resistivity and seismic methods, electromagnetics. It employs a wave propagation reversal procedure that compensates for energy absorption.
Chapter 4 of the senior seismic hazard analysis committees sshac report, entitled methodology for characterizing seismic sources, describes the key elements of a seismic source characterization ssc. In this study, an investigation using an inverse q filter with and without stabilization on synthetic and 3d land seismic data was carried out. The instability of conventional full inverse q filtering is overcome through adding a stabilization factor to the wavefield continuation, and a good application effect is achieved. Full modeling software 2d, 3d, and 4d seismic survey design, processing, and modeling are created using industry and proprietary software packages. Highresolution seismic data are prerequisite for reservoir characterization. Pdf seismic migration with inverse q filtering yanghua. Postmigration inverse q filtering to enhance amplitude. A futtermantype absorptiondispersion model is used. Compensating for attenuation by inverse q filtering carlos a. Free geophysics books download ebooks online textbooks.
Netl university coalition for fossil energy research newsletter. Pdf seismic wave dispersion effects and inverse qfilter. The method was implemented in a layered manner, assuming a depthdependent, layeredearth q model. We use this work to successfully to improve the resolution of the three dimensional 3d pp and psv seismic. Review of recommendations for probabilistic seismic hazard. However, the earths q filtering effect inevitably induces the energy dissipation of highfrequency wave components, and distorts the seismic wavelets, simultaneously futterman 1962, anderson et al1977, kjartansson 1979, wang and guo 2004. Improve q estimates with spectrum correction based on. The seismic trace is the combination of both signal and noise, the signal wanted data is the representation of the geologic feature but the presence of noise shows it different from real. If you continue without changing your browser settings, you consent to our use of cookies in accordance with our cookie policy.
We present here a stabilized algorithm for such a migration incorporating inverse q filtering scheme, so that the imaging technique is. This paper presents a stable, efficient approach to inverse. Methods of processing seismic data to remove unwanted noise from meaningful reflection signals are provided for. Wang 2006 studied the influences of inverse q filtering. Researchers have successfully improved the time resolution of seismic data using proper inverse q filtering wang, 2002. Q filter dug insight 4 user manual dug insight user manual. The qertm results for noise free data are carried out over a simple layered model and a more realistic marmousi. This results in frequencydependent seismic attenuation reduced amplitude of. For each individual constant q layer, the seismic wavefield recorded at the surface is first extrapolated down to the top of the current layer and a constant q inverse.
An inverse q filtered migration algorithm performs seismic migration and inverse q filtering simultaneously, in which the latter compensates for the amplitudes and corrects the phase distortions. Baseline assessment of seismic hazards in british columbias north coast. Then, we show two field examples of using this software for pwave arrivaltime. Attenuation and dispersion can be quantified by seismic quality factor q. It has been extensively tested since 2012 for matlab r2010a and newer versions. Estimation of q and inverse q filtering for prestack. This paper presents an analytical study of the complete transform of improved gabor wavelets igws, and discusses its application to the processing and interpretation of seismic signals. In seismic wave propagation, both the amplitude attenuation and the phase distortion are the exponential functions of the frequency and the travelling time. Download product flyer is to download pdf in new tab. The methods comprise the steps of assembling seismic data into common geometry. Seismic inverse q filtering is a dataprocessing technology for enhancing the resolution of seismic images. Pdf a principal limitation on seismic resolution is the earth attenuation, or qeffect. Seismic inverse q filtering employs a wave propagation reversal procedure that compensates for energy absorption and corrects wavelet distortion due to velocity dispersion. Multicomponent seismic exploration technology, combining reflected pp and converted pswaves, is an effective tool for solving complicated oil and gas exploration problems.
A practical approach is adopted, with values per layer per ray type qp, qsv, sh rather than a full anisotropic q treatment. Compensating for attenuation by inverse q filtering. It is implemented in a layered manner, assuming a layeredearth q model. However, as discussed in wang, a key problem with inverse q filtering. Validating an earth model by simulating a migration image is an important step. Filtering of seismic data the interpretation of seismic data is made purely on the basis of what is observed in the final processed section. Seismic inverse q filtering is part of wikiproject geology, an attempt at creating a standardized, informative, comprehensive and easytouse geology resource. Its major axis of motion is in the vertical direction. However, there are strong artifacts as the qvalue decreases and the imaging time increases, even though the input signal is noise free. An approach of inverse q filtering considering time. Seismic data random noise attenuation using dbm filtering. Synthetic and real data are shown to illustrate both amplitude and phase inverse q filtering of seismic reflection records.
Q estimation from reflection seismic data for hydrocarbon. Seismic inverse q filtering by yanghua wang overdrive. Aseismic definition of aseismic by the free dictionary. Introduction l the quality of seismic volumes is critical in building reliable reservoir models. A principal limitation on seismic resolution is the earth attenuation, or q effect, including the energy dissipation of highfrequency wave components and the. Properties of an improved gabor wavelet transform and its. Stabilized inverse q filtering is a data processing technology for enhancing the resolution of reflection seismology images where the stability of the method used is considered.
Enhanced downhole microseismic processing using matched filtering analysis mfa authors. Inverse q filtering via synchrosqueezed wavelet transform. The phase spectrum of the inverse q filter usually is assumed to be minimumphase, which can be computed by taking the hilbert transform of the amplitude spectrum appendix b. However, it is also possible to develop an inverse q filter from the forward filter 1. Feb 01, 2010 an earth model is used in a collaborative environment in which some members provide information for its construction and others utilize the result. Seismic inverse q filtering,, is a process targeted at inverting phase and amplitude distortions of the propagating and reflected acoustic waves. By compensating for amplitude attenuation, seismic data can provide true relativeamplitude information for amplitude inversion and. Seismic inverse q filtering is a data processing technology for enhancing the resolution of seismic images. Planning for a hpc seismic data processing facility external network hooks secure internet access and external network connectivity using vpn are present in most of the dpc environments. The instability of conventional full inverse q filtering.
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