The technique allows geophysicists to infer critical information that cannot be obtained otherwise. In particular, the course stresses regularization methods for inverse problems that arise in the inversion of seismic data, noise elimination and reconstruction of seismic surveys. We do this with seismic unx su, a free software package maintained and distributed by the center for wave phenomena cwp at the colorado school of mines csm. Application to groundroll attenuation seismic data always consist of signal and noise components. For example, a bandpass filter in the domain filters out higher temporal frequencies by setting them to zero. It includes allows gather attributes, seismic ava and avo analysis plus stack rotation.
I, crosscorrelation optional for vibration data, chap. Access the industrys largest volume of geoscience data through tgs cloudbased web portal, r360. Gather attributes seismic ava and avo analysis stack. Seismic data, imaging, well data and reservoir reports from the experts at tgs. Such things as frequency content, gain, trace spacing, and type of display are all up for grabs see displaying seismic data. Seismic section from malacca strait survey, a original seismic data, b seismic data after processing, c original seismic data in fk domain, and d filter design in fk domain. Simple being free of charge is not sufficientsee gratis versus libre.
We applied fk filter with two different cutting techniques in four different processing flows to show its effect on seismic data. The fundamental parameter is the slope of the velocity which is desired to be removed or kept. Comparison of fk and svd filtering in the processing of a. Median filtering techniques for attenuation of linear.
Bridging the gap between modern image processing practices by the scientific community at large and the world of geology and reflection seismology. Broadband seismic data filtering using the wavelet transform and the fk filter. Introduction to the processing of seismic reflection data within reflexw in the following the complete processing of seismic reflection data is described including import of the seismic data chap. Fx linear prediction filtering of seismic images mark p. Pdf application of fk filtering for coherent noise. This unwanted signal were generated by various sources and therefore had their own noise characteristic. The cutoff frequencies for the fk analysis coincide with the edges of the used bandpass filter discussed in chapter 5. Pdf random and coherence noise attenuation complete. Pdf on the broadband seismic data filtering using the wavelet. This tool derives a model sinusoid of some fixed frequency and adaptively determines both its amplitude and petroleum africa december 2010 47 technology and solutions a seismic processing noise attenuation techniques for relative amplitude processing. The paper aims to present a twodimensional land seismic processing, involving two flowcharts, ranging from the pre processing to the stage of poststack migration. Fk filter for the suppression of non desired waves.
Deghosting and designature removing the seismic ghost. The first filter used was fk filter, which is a two. Ground roll is the main type of coherent noise in land seismic surveys and is characterized by low frequencies and high amplitudes. It is thus understandable that considerable time and effort is expended in any processing project on the final parameters of seismic display so as to satisfy the individual tastes of the interpreter. Our goal is to give you the experience and tools to continue exploring the concepts of seismic data processing. Mvsp is a new matlab tool with a graphical user interface gui for vsp shot modeling, data processing, and interpretation. As proved by the application to synthetic noise data, this technique. As you can see from the rms amplitude plots, one of the traces has extreme values. This course covers practical aspects of signal theory and inverse problems with application to seismic data processing.
Notice that free and opensource requires that the source code is available. It would be pertinent to add here that the backscatter is generally also addressed well by two runs of fk filtering,one run in the common shot followed by another in the common median filtering techniques for attenuation of linear noise in seismic data. Borehole seismic data processing and interpretation. Cmp processing greatly enhances the signal to noise ratio and allows coherent reflections to be visible. Noise attenuation is an essential phase in seismic processing data, usually resulting in seismic. Dec 23, 2015 ali added it dear sir ozdogan, i need to your book seismic data processing, if you give me one copy hard or soft. Processing, inversion and reconstruction of seismic data. Vista software is used to accomplish seismic processing flows which applying on it. For these signals the fk diagram is computed as an integration over all frequencies in a chosen frequency band. Gangaiah, ongc summary india is a peninsular country which is surrounded by sea in three sides, having huge offshore environs in its periphery. Seismic data processing, 1987 and seismic data analysis, 2001. 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. To remove undesirable portions of data during seismic processing to increase the signaltonoise ratio of seismic data. It is possible to produce twodimensional fourier transforms of twodimensional data sets, such as rectangular aeromagnetic and gravity maps.
Enhance seismic interferometry signal using an adaptive fk. Agc is commonly used in seismic processing to improve visibility of latearriving events in which attenuation or wavefront divergence has caused amplitude decay. Highly aliased groundroll suppression using a 3d multiwindow kl filter. Extensive noise attenuation of shallow water 3d seismic. Seismic data interpretation using digital image processing. Some signal enhancement programs are used prestack before stacking and some are used poststack after stacking. Groundroll noise suppression in land surface seismic data. Application of fk filtering for coherent noise removal in high. Fk filtering for seismic data processing by adithya shashidhara shettar. This book treats the processing of a subset of seismic data, those in digital forms. Seismic processingnoise attenuation techniques for. In land, seismic data have usually a high level of surface waves. This book covers the basics of seismic exploration, with a focus on image processing techniques as applied to seismic data.
Pdf processing seismic data with open source software. Enhance seismic interferometry signal using an adaptive fk filter. The seismic data used in this paper is represented 2d seismic line in razzak field it is razaak 18 87 in seg y format. The flowcharts differ mainly in the filtering stage, through by different streams. Filtering can be used to separate out a particular seismic event, which is. The acquisition of the shallow marine seismic survey were done using a sparker source to obtain a high frequency seismic data. Marfurt abstract while modern recording capacity facilitates dense seismic acquisition, many, if not most, legacy 3d land surveys are spatially aliased with respect to groundroll. Get in contact with downunder geosolutions for more information.
Published contributions books, articles, reports go back to. Introduction to the processing of seismic reflection data. Technologys monochromatic filter provides an alternative that retains the primary signal. The timefrequency denoising algorithm is an effective method for handling noise problems elboth et al. Fk filter after editing and mute of trace amplitudes, commonly in seismic processing flow chart, it recommends some kind of filtering. Image processing techniques can be used for filtering certain spatial wavelengths in the data or for passing structures with certain geographical. This is useful for inspecting the spatial frequencies in the north and east directions. Contents introduction to filtering types of filters fk filter weiner. Application of fk filtering for coherent noise removal in. The use of seismic reflection to study earth subsurface is commonly troubled by the presence of the coherent noise in the seismic data. Seismic sections or slices resulting from the processing of 3d data can often be enhanced by the application of various filters. Application to a legacy mississippi lime survey sumit verma, shiguang guo, thang ha, and kurt j. One method of supplying a partially sorted array to the sorting algorithm is to use the sorted 2d data box of the previous time sample and replace only the new locations with the data values at the current time location refer fig. Filtering of seismic data the interpretation of seismic data is made purely on the basis of what is observed in the final processed section.
The fk diagram of a real p arrival recorded at yka jul1994 10. Pgs offers a complete set of deghosting solutions comprising both acquisition based and processing based techniques or a combination of both. Acquisition and processing of marine seismic data sciencedirect. I want to look at the data in the frequencywavenumber fk domain so i can filter out some of the signal, as velocities that overlap in the timespace domain are distinct in fk domain. If you continue without changing your browser settings, you consent to our use of cookies in accordance with our cookie policy. The first filter used was fk filter, which is a two dimensional filter defined in the frequency domain obtained by double fourier transform. 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. The fk response when applied it on 2d seismic data from. This chapter represents a brief introduction to seismic data processing and. Good morning jazz relaxing background bossa nova jazz playlist have a nice day.
Filtering can eliminate certain frequencies, amplitudes or other information. The seismic unix package supplies the sudipfilt dipslope filter which uses the fk spectrum to separate out events with different apparent velocities investigate the parameters of sudipfilt using. Adaptive groundroll filtering david le meur cggveritas, nigel benjamin cggveritas, rupert cole petroleum development oman and mohammed al harthy petroleum development oman summary the attenuation of surface waves while maintaining a friendly preservation of the body waves is a difficult goal to achieve in land data processing. An adaptive fk filter is implemented to enhance reflectivity extracted from ambient noise data. Prepare a book on the unconventional reservoirs caracterization using the artificial intelligence. Broadband, filtering, seismic, wavelet transform, fk filter. There are over 68 seismic processing careers waiting for you to apply. However, the data that goes into the cmp processing is often contaminated with noise. We show how the dispersed pseudorayleigh waves characterized by low apparent velocity and by low frequency contents can be filtered in. This novel filter enables us to use the processed seismic data for waveform. The lowstress way to find your next seismic processing job opportunity is on simplyhired.
The image gather processing module provides an indispensable toolkit for analysing and processing image gathers. Where sgf is the ghostfree source signature, gs is the source ghost, gr is the receiver ghost and r is the instrument filter. The first tool is a frequencywavenumber fk filter, a twodimensional filter. The application of fk filter were used to eliminate this unwanted noise using the data obtained from the malacca strait and terengganu bay. When 3d land data is acquired a shot record is fired into a number of parallel receiver lines with the source point typically towards the center of the spread as shown in this diagram. The reader interested in freeware just free of charge software is referred to the list of freeware geophysics software. Our objective is to introduce you to the fundamentals of seismic data processing with a learnbydoing approach. This however results in a stronger noise level in the recorded data. The standard fk filter is a 2d filter fkk filtering applies a 3d filter. Another example is coming from terengganu survey, where all the survey parameters during. Apply an fk filter, however, and you get a nasty result. Seismic data always consist of signal and noise components. Hi, i have timespace data from several stations in a linear array. Extensive noise attenuation of shallow water 3d seismic data in kg offshore, india k.
4 614 1429 1415 121 215 308 1172 1289 1102 1592 367 511 992 1358 22 1030 1285 566 795 250 38 857 372 413 569 489 471 1264 1267