Improving signaltonoise through multiple attenuation and statics determination, frequency filtering and coherency enhancement. Reflections on the deconvolution of land seismic data. Seismic inverse q filtering employs a wave propagation. Gverse geophysics software is a powerful, fully integrated 2d and 3d seismic interpretation system that provides a full range of fitforpurpose interpretation capabilities, attribute analysis, and mapping tools.
However, the data that goes into the cmp processing is often contaminated with noise. On the other hand, the filtering process in the time domain involves convolving the filter operator with the input time series. We needed a worldclass enablement platform to create one unified system for both partners and direct sellers. Wang has written an excellent book on the subject of inverse q filtering, seismic inverse q filtering 2008, and discuss the subject of stabilizing the method. Improving the stationary character of the seismic trace is an important step in obtaining the best possible seismic image. Searched for inverse q filtering in all fields 1 results found d. The result of combining vertical inverse filtering with transverse inverse filtering is. Seismic inverse q filtering is a data processing technology for enhancing the resolution of seismic images.
When a seismic waves or energy propagate through the earth, they are. The time domain filtering dialog box is used to apply this filter to the dataset. In addition to the developments in all aspects of conventional processing, this content represents a comprehensive and complete coverage of the modern trends in the seismic industryfrom time to depth, from 3d to 4d, from 4d to 4c, and from isotropy to anisotropy. The idea is that this will undo the effects of a previous filter, such as the earth or the recording system. A variant of seismic reflection used at the surface of water bodies is subbottom profiling or imaging. Spectral analysis and filtering with the wavelet transform.
That is the reason why inverse filtering the signal is usually not a good. Seismic reflection methods environmental geophysics us epa. It is based on the inverse filter design by bob mcclure. Contamination of seismic reflection records at early times by firstorder water reverberations can be especially severe during survey operations over hard and flat sea floors on the continental shelf or in lake environments.
Canary systems vertically integrated solutions for data acquisition allow for the seamless combination of seismic or microseismic data with other sensor types in a single platform, and has been applied successfully in many projects across different markets, including in dam safety, mining, and structural monitoring. In mathematics, deconvolution is an algorithmbased process used to enhance signals from. The inverse filter is formed from zeros equal to the estimated resonant poles. This procedure makes rapid, continuous reflection soundings of the units below. The solution can be computed efficiently in the fourier domain and amounts to the coefficientwise division 5 x. To obtain a solution when we make computations with a seismic model we always have to. Q is the anelastic attenuation factor or the seismic quality factor, a measure of the energy loss as the seismic wave moves. Seismic inverse q filtering is a data processing technology for enhancing the. Seismic inverse q filtering by yanghua wang seismic inverse q filtering by yanghua wang pdf, epub ebook d0wnl0ad seismic inverse q filtering is a data processing technology for enhancing the resolution of seismic images. Reflections on the deconvolution of land seismic data cseg.
Seismic inverse q filtering by yanghua wang pdf, epub ebook d0wnl0ad seismic inverse q filtering is a data processing technology for enhancing the resolution of seismic images. Deconvolution can also be performed on other types of data, such as gravity, magnetic or well log data. One of his specialties is processing and writing software for multicomponent seismic data. Seismic inverse q filtering yanghua wang download here seismic inverse q filtering is a data processing technology for enhancing the resolution of seismic images. Application of inverse q filtering to land seismic data to improve signal where there is no vsp data control r. Frequencydomain filtering involves multiplying the amplitude spectrum of the input seismic trace by that of the filter operator. The advantage of this technique is the ability to tow the seismic source on a sled or catamaran and to tow the line of hydrophones. Seismic processing often involves several stages of deconvolution, each of a different type and with a different objective.
This data provides valuable insight about patterns of stress distribution, rock mass, faults. Improving resolution through deterministic and statistical deconvolution. It corresponds to maximumlikelihood estimation in the presence of gaussian noise. Seismic migration with inverse q filtering, geophysical. Estimation of q and inverse q filtering for prestack. Seismic inverse q filtering by yanghua wang overdrive. This web page views the wavelet transform largely in the frequency domain.
Data fusion for resolution improvement by combining seismic. Inverse q filter for seismic resolution enhancement seg library. Tikhonov with 1snr noise is destructive away from focus 4dofs utilized a priori knowledge of depth of each digit artifacts due primarily to noise getting amplified by the inverse filter deconvolution in the presence of noise snr10. Signal processing data analysis and graphing software. A new dereverberation scheme based on two classical techniques predictive deconvolution and velocity filtering has been developed to address this. Origin supplies a fft filter tool to select frequency components from an input signal by a specific filter type. Seismic and microseismic monitoring plays an important role across many engineering disciplines. However, inverse filtering is very sensitive to additive noise. The inverse filtering is a restoration technique for deconvolution, i. It is found that the fx filter, when applied to noisefree synthetics, produces little or no attenuation of continuous layers, but does laterally smear sharp discontinuities. Seismic processing, deconvolution, filter operator, reflectivity, desired output and actual output. Geophysics software seismic interpretation software. Whatever poles are chosen for the leastdamped part, and however they are computed provided they are stable, the damped part can be computed from the full impulse response and parametric part using inverse filtering, as illustrated in the computed examples above.
Seismic quality is poor large bandwidth to the data, but most of the high frequency signal is most probably noise high frequency component cannot be modeled in the well logs welltoseismic tie is poor, which leads a poor inversion result filtering the seismic data produces a better welltoseismic tie, but produces a. Inverse q filtering is a method to restore the energy loss due to energy dissipation amplitude compensation and to correct the timeshift of the data due to velocity dispersion. He was an associate editor seismic processing of geophysics from 19982001. Opendtect, and the processing is performed with geoview software form. This website beta version contains information on geophysical methods, references to geophysical citations, and a glossary of geophysical terms related to environmental applications. 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. Pdf processing seismic data with open source software. Seismic inverse q filtering is a data processing technology for enhancing the resolution of reflection seismology images. Sales enablement global leader seismic sales enablement. Spectral analysis and filtering with the wavelet transform introduction a power spectrum can be calculated from the result of a wavelet transform. Apr 20, 20 seismic inverse q filtering yanghua wang. Jan 26, 2009 seismic inverse q filtering is a data processing technology for enhancing the resolution of seismic images. Data fusion for resolution improvement by combining. Curvelet transforms and filtering of seismic attributes for reservoir modeling.
Seismic quality is poor large bandwidth to the data, but most of the high frequency signal is most probably noise high frequency component cannot be modeled in the well logs welltoseismic tie is poor, which leads a poor inversion result filtering the seismic data produces a. Learn more reconstructing image by inverse filter issue in matlab. Fft2d forward or inverse 2d fourier transform fft ifft1d inverse 1d fourier transform fft. Nov 01, 2004 seismic migration with inverse q filtering seismic migration with inverse q filtering wang, yanghua. Plotting the power spectrum provides a useful graphical representation for analyzing wavelet functions and for defining filters.
The actual output from the wiener filter using optimum delayed spike shows the most possible. Filtering is commonly used in signal processing to filter out unwanted features and reveal components of interests. Roy ongc, geophysical services, chennai summary the effect of dispersion and attenuation on land seismic data can be removed by applying inverse q filtering thus. Deconvolution, or inverse filtering, can improve seismic data that were adversely affected by filtering, or convolution that occurs naturally as seismic energy is filtered by the earth. Submitted in partial fulfillment of the requirements for the degree of. An inverseq filtered migration algorithm performs seismic migration and inverseq filtering simultaneously, in which the latter compensates for the amplitudes and corrects the phase distortions. Pdf mixedphase inverse filtering of seismic data researchgate. The programs provided allow it to operate as an integrated data management terminal which automatically collects. Seismic migration with inverse q filtering seismic migration with inverse q filtering wang, yanghua. This filter can be used to extend the natural period of a sensor.
Equation implies that the inverse filter converts the basic wavelet to a spike at t 0. The backbone of the software architecture is a library that contains the numbercrunching elements of the deconvolution task. For each of these filtering techniques, tests of the various parameters. The application of this inverse filtering can not recover lost information, but can effectively. Oz yilmaz has expanded his original work on processing to include inversion and interpretation of seismic data. The improvement of converted wave resolution is one of the key problems. Cmp processing greatly enhances the signal to noise ratio and allows coherent reflections to be visible. Therefore, the filter operator ft needed to compute the earths impulse response from the recorded seismogram turns out to be the mathematical inverse of the seismic wavelet wt. Filtering of seismic data the interpretation of seismic data is made purely on the basis of what is observed in the final processed section. A forward q filtering is used to test attenuation and dispersion effects generally on synthetic data, and an inverse q filtering is used to remove them from seismic data. Likewise, the inverse filter converts the seismogram to a series of spikes that defines the earths impulse response. Fx linear prediction filtering of seismic images mark p. Data fusion for resolution improvement by combining seismic data with logging data. Compensating for attenuation by inverse q filtering.
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. The main factor affecting converted wave resolution is the absorption of seismic waves in overlying strata. For the purpose of tandem inverse filter of expanding frequency band, we apply borehole seismic trace in well a as an expected output signal, and arbitrary poststack seismic trace between well a and well b as an input signal, then superimpose a transverse inverse filter calculated from each seismic record with previous vertical inverse filter. Inverse filtering physical audio signal processing. Introduction seismic migration is an effective imaging technique used extensively in geophysics investigation. Multicomponent seismic exploration technology, combining reflected pp and converted pswaves, is an effective tool for solving complicated oil and gas exploration problems. It employs a wave propagation reversal procedure that compensates for energy absorption and corrects wavelet distortion due to velocity dispersion.
Inverse q filtering is an important dataprocessing procedure broadly used for enhancing. Dereverberation of marine reflection seismic data by a. The concept of deconvolution had an early application in reflection seismology. The original time domain data is converted to frequency domain by applying forward fourier transformation to make processing easy and filtering. Curvelet transforms and filtering of seismic attributes. By compensating for amplitude attenuation, seismic data can provide true relativeamplitude information for amplitude inversion and. A step in seismic signal processing to recover high frequencies, attenuate multiples, equalize amplitudes, produce a zerophase wavelet or for other purposes that generally affect the waveshape. The methods investigated here include bandpass filtering, inverseq filtering, and radon filtering. In this paper, seismic inverse qfiltering is implemented in a stabilized manner to produce highquality data in terms of resolution and sn ratio. See inverse filter for seismic sensors for more information. Frequency filtering basically seismic data processing is done in the frequency domain. This outline is almost the inverse of the order of the processing.
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