The precision of seismic reflection data does not fulfil to explore private and complex structure oilgas pools. Pdf inverse qfilter for seismic resolution enhancement. Compensating for attenuation by inverse q filtering. When the roles of the arrays in table 14 are interchanged, the output array in table 16 results. Kurahashinakamura et al ocean reconstruction from sparse data question of whether the strength of the amoc was larger or smaller in the lgm than in the modern day climate is still. Seismic inverse q filtering yanghua wang download here seismic inverse q filtering is a data processing technology for enhancing the resolution of seismic images.
Seismic data random noise attenuation using dbm filtering boll. An inverse qfilter algorithm based on stable wavefield. Figure 3a shows the stack section before inverse q filtering and figure 3b the same section after the filtering. Reflections on the deconvolution of land seismic data. Geostatistical filtering allows the removal of acquisition footprints, patterns due to oriented picking, white or coherent noise on velocities or amplitudes. 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.
Enhanced downhole microseismic processing using matched filtering analysis mfa authors. Filtering and quality control are possible on 2d3d gridded data but also on scattered data such as seismic picks. 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. Based on the expression of amplitude attenuation and phase velocity dispersion proposed by futterman, and considering the wellseismic matching, we derived the expression of seismic wave velocity dispersion between phase velocity and amplitude spectrum for the following four cases. Efficient exploration through bayesian deep qnetworks. 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. An investigation of the tools of seismic data processing. The mechanics of convolution are described in table 15. Enhancing time resolution by stabilized inverse filter and.
If checked, this will generate apparent dispersion curves instead of the fundamentalmode m0 curves by accounting for the mode jump during the theoretical dispersion curve generation. Express letter parametrization of general seismic potency. It experienced an upsurge in popularity in the late 1980s. Seismic migration with inverse q filtering seismic migration with inverse q filtering wang, yanghua. Introduction to neural networks portland state university.
In this paper, we present a method to estimate the swave q values from prestack converted wave gathers. Reflections on the deconvolution of land seismic data cseg. Seismic data random noise attenuation using dbm filtering. The earth filter, considered as a minimum phase process, could be represented by a q model where q denotes the quality factor of the medium. Eidsvik norwegian university of science and technology summary subsurface velocity inversion using full waveform modelling continues to be a challenging problem. P assiveseismic methods provide an effective surveillance technology for.
Contact us for more information about nodalseismic and our approach to seismic data acquisition. Note in particular that the ai is much cleaner, and retains good structural conformance. In this paper, we apply the stabilised inverse q filter to carbonate reservoirs, to characterise the fractures and cavities of the ordovician carbonate reservoirs. An investigation of the tools of seismic data processing monika wadhawan, priyanka midha, inderjeet kaur and savita department of geophysics kurukshetra university kurukshetra, india summary the purpose of seismic data processing is to isolate signal i. Inverse qfiltering 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. Extracting meaningful information from seismic attributes. This was a result of the discovery of new techniques and developments and general advances in computer hardware technology. Seismic inverse q filtering is a data processing technology for enhancing the resolution of seismic images. Constant q model inverse q filter approaches inverting the q matrix downward continuation pseudodifferential operators comparison of the methods.
Enhanced downhole microseismic processing using matched. Application of inverse q filtering to land seismic data to. It is similar to apply the q analysis method on the prestack data after nmo. Pdf seismic wave dispersion effects and inverse qfilter. The vertical resolution box 1 is derived from the length of the soundwave and layers can be discerned when their thickness is below. Connect with us brochure latest news event calendar careers. Note that in this case, the impulse response is unknown and is of primary interest hence reflection processing deals with inverse filtering i. Seismic migration with inverse q filtering, geophysical. Furthermore, we extend a stable and effective poststack inverse q filtering method to prestack data which uses wave field continuation along the ray path to compensate for attenuation in prestack common shot pp and pswaves. An inverse q filtering procedure attempts to remove the q effect to produce highresolution seismic data. Tracetransformbased timefrequency filtering for seismic signal enhancement in northeast china. Introduction to neural networks development of neural networks date back to the early 1940s. Extracting meaningful information from seismic attributes cseg.
In linear inverse filtering, for a given vocaltract configuration the acoustic effect of the supraglottal vocal tract is canceled by a linear, timeinvariant filter having a transfer characteristic that is the inverse of that of the supraglottal system. An inverse q filter when applied to data will increase the signal bandwidth and correct the signal amplitudes thus improving the reliability of data. Determination of teleseismic relative phase arrival times using multichannel crosscorrelation and least squares. Filtering of seismic data the interpretation of seismic data is made purely on the basis of what is observed in the final processed section. Then, the applied probabilistic approach maps the posterior pdfs for the hypocentral coordinates, the moment tensor, and the source time function. 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. The accurate determination of q may provide a more accurate amplitudeoffset analysis and reliable seismic inversion for reservoir characterization. General discretegeneral discretetime model of time model of. On the inverse filtering of speech university of crete.
However, the data that goes into the cmp processing is often contaminated with noise. Convolution two important cases of interest digital signal filtering earths response is also a filter. Contact us for more information about nodalseismic and our approach to seismic data acquisition about nodalseismic. This paper focuses on varying the filtering direction of the 2d tfpf and proposes a cc trace transform to find the optimal temporalspatial radial traces in the seismic record. Jul 30, 2014 we explained the necessity of inverse q. Thus, in practice, attempts are first made to estimate a q model for the subsurface. Therefore, the accurate estimation of q is a core challenge to overcome before applying inverse q filtering, considering that q does not depend linearly on frequency kolsky, 1956. It employs a wave propagation reversal procedure that compensates for energy absorption and corrects wavelet distortion due to velocity dispersion. Express letter parametrization of general seismic potency and moment tensors for source inversion of seismic waveform data lupei zhu1 and yehuda benzion2 1department of earth and atmospheric sciences, saint louis university, st. However, the instability of the amplitude compensation restricts the application of this method in. Mar 14, 2009 in this paper, we present a method to estimate the swave q values from prestack converted wave gathers.
Can sparse proxy data constrain the strength of the. 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. Enhanced downhole microseismic processing using matched filtering analysis mfa. The results for processing the prestack seismic data indicated that the inverse q filter method can improve peak frequency and frequency bandwidth.
Cmp processing greatly enhances the signal to noise ratio and allows coherent reflections to be visible. To achieve this, we used the inverse q filter methods to improve the resolution for the seismic data. Thus, in practice, attempts are first made to estimate a qmodel for the subsurface. So we need to improve the resolution of seismic data.
Q is the anelastic attenuation factor or the seismic quality factor, a measure of the energy loss as the seismic wave moves. In the vector scheme, a column vector v is built by the rows of matrix i as shown in eqs. Gabor deconvolution of seismic data for source waveform and q. Improving prestack seismic data resolution based on inverse. However, the instability of the amplitude compensation restricts the. We are a data acquisition contractor that specializes in the unique and strategic operation of a completely cablefree seismic recording system. The inverse q filtered section shows higher dominant frequency than the other. Seismic migration with inverse q filtering wang 2004. Based on the expression of amplitude attenuation and phase velocity dispersion proposed by futterman, and considering the well. Twodimensional 2d seismic data is normally used to get a regional overview in an area. Gabor deconvolution of seismic data for source waveform. The inverse q filtering is a useful method for the compensation of stratigraphic absorption. Simultaneous inversion of multiple microseismic data for. Convolution and filtering university of saskatchewan.
It is implemented in a layered manner, assuming a layeredearth q model. Seismic data quality control and filtering geovariances. Nava abstract we have applied bayesian inference for simultaneous. In this paper we present a stable approach to inverse qfiltering, based on the theory of wavefield downward continuation. Seismic resolution is a measure of how large an object need to be in order to be seen in seismic. Bayesian waveform inversion for moment tensors of local. The difference results from the use of the fx deconvolution, and the proposed methods are shown in fig. Compensating for attenuation by inverse q filtering carlos a. Grossman, and victor iliescu, the university of calgary summary we present a novel approach to nonstationary seismic deconvolution using the gabor transform.
Introduction seismic migration is an effective imaging technique used extensively in geophysics investigation. The results for processing the prestack seismic data indicated that the inverse q filter method can improve peak. In this paper we present a stable approach to inverse q filtering, based on the theory of wavefield downward continuation. The stabilised inverse q filtering method has been successfully applied to the clastic rock strata for the sand body description and oilgas prediction gan et al. Nonlinear inverse filtering technique for estimating the. Seismic inverse q filtering is a data processing technology for enhancing the resolution of reflection seismology images. For each individual constant q layer, the seismic wavefield recorded at the surface is first extrapolated down to the top of the current. Application of inverse q filtering to land seismic data to improve signal where there is no vsp data control r. Tracetransformbased timefrequency filtering for seismic. Enhancing time resolution by stabilized inverse filter and q. Simultaneous inversion of multiple microseismic data for event locations and velocity model with bayesian inference zhishuai zhang 1, james w. Gabor deconvolution of seismic data for source waveform and q correction gary f. Nov 01, 2004 read seismic migration with inverse q filtering, geophysical research letters on deepdyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips.