Bandlimited seismic inversion pdf

Pdf band limited impedance inversion of blackfoot field, alberta. Inversion of bandlimited reflection seismograms ieee xplore. The bandlimited inversion appears to produce a more detailed acoustic impedance model than the modelbased inversion. Manani exploration division arabian gulf oil company benghazi libya p. For both deterministic and stochastic inversion, the seismic amplitudes control intermediate frequencies within the seismic bandwidth. Seismic inversion and reservoir characterization, nc73, sirt. Seismic inversion provides insight to porosity variations away from limited well control. Simultaneous inversion of prestack seismic data can be particularly useful for analyzing data with avo anomalies. Ranero 1,2 1barcelona center for subsurface imaging, institute of marine sciences icm, csic, 08003, barcelona, spain.

Traditionally, inversion has been applied to poststack seismic data, with the aim of extracting acoustic impedance. In the same way most of the seismic inversion methods are modeldriven because they use an initial solution and try to fit the real solution from the initial. Both issues can be largely overcome by using constraints and integrating prior information. Each type of seismic inversion has its own advantages to display the coal seam and its characteristic.

Seismic inversion is essentially a very simple procedure. Interwell seismic inversion and reservoir characterization. The inversion analysis tool shows the resulting inversion trace at each well location, overlain on top of the original impedance logs. Acoustic impedance inversion of vintage seismic data over. Investigating the low frequency content of seismic data. Seismicinversionmethodsacasestudyfromblackfootfield,canada. Then why are high frequency components are not taken into account during inversion. Porosity prediction from seismic inversion, lavrans field. An overview of fullwaveform inversion in exploration. Margrave abstract this paper describes a seismic inversion method which has been cast as a matlab algorithm called blimp band limited impedance.

Welltoseismic tie wavelet estimation a good tie correlation coefficient between the real and synthetic seismic trace greater than 85%, is necessary to estimate the wavelet properly. Recovering low frequencies for impedance inversion by. Quantifying shallow seismic anomalies, published in aapg explorer. Using seismic inversion and net pay to calibrate eagle ford shale producible resources bo chen 1, dhananjay kumar, anthony uerling2, sheryl land2, omar aguirre2, tao jiang1, and setiawardono sugianto1. Because of the stateoftheart performance of machine learning in many elds, geophysicists have begun adapting such ideas in seismic processing and interpretation chen et al.

We then combine the information from the seismic data with controlling information from the seismic model and produce a final inversion result. Inherently, seismic data is missing low frequency data which must be supplied by other means. Interwell is a seismic inversion and characterization software for reservoir and exploration geophysicists, available in linux and windows environments. The position of the crossplot zones on the seismic stack of figure 2, gas zone red.

Box 263 summary geophysical inversion involves mapping the physical structure and properties of the subsurface of the earth using measurements made on the surface of the earth. The deep neural network dnn is trained to automatically recover the missing low frequencies from the input bandlimited data. Extrapolated full waveform inversion with deep learning. Low frequency modeling and its impact on seismic inversion data any deviation from this shale trend is an anomalous signature. Analysis of the inversion of sparse spike model, based model, and bandlimited model for charecterization of sand stone reservoar using log and seismic data, in stratton field, south texas, usa abstrack by nur indah safitri acoustic impedance directly describes the physical character in the rock layer and. This new proposed method is essentially a modified blimp band limited. Interpreting bandlimited elastic ip, is volumes from pre. Workshop on geophysical data analysis and assimilation. Again, notice the excellent delineation of the gas sand. Appreciate the various factors in simultaneous inversion introduce errors and bias.

A simple algorithm for bandlimited impedance inversion. Basis pursuit inversion figures 1b and 2b show the synthetic traces, which are a result of convolution between the wavelet and the re. Acoustic and elastic impedance models of gullfaks field by. Poststack inversion transforms a single seismic data volume into acoustic impedance through integration of seismic data and well data. Bandlimited inversion analysis using elastic initial impedance model is shown in a and inverted model is shown in b. Enhancing the quality of seismic impedance data, published in aapg explorer. Pdf the interest in seismic inversion techniques has been growing steadily over the last couple of years. Here are some of the papers that we have published on seismic inversion. Siam journal on scientific and statistical computing. Seismic inversion and reservoir characterization, nc73.

A basic assumption in our inversion is that each seismic trace is a bandlimited representation of the true reflectivity function. Seismic absolute acoustic impedance inversion with l1 norm. This research uses three inversion methods, which are. Final elasticparameter models optimally reproduce the input seismic, as this is part of the seismic inversion. Pdf band limited impedance inversion of blackfoot field. Impedance inversion has been carried out in the time domain for the last four decades.

Lateral and vertical discrimination of thinbed fluvial. Full, threedimensional algorithms are incorporated for scalar, acoustic, and elastic wave equations. Seismic inversion and well analysis are done to determine the coal seam characteristics of muara enim formation. Lindseth 1979 suggested that information from a nearby well log could be used to provide this missing lowfrequency component. New modified band limited impedance blimp inversion method. The old and the new in seismic inversion cseg recorder.

Impedance inversion method, in which the ai logs for blimp. New insights for cbm reservoir modelling on muara enim formation, south sumatra faris mohamad noor and agra adiptathis content was downloaded from ip address 157. An overview of fullwaveform inversion in exploration geophysics j. Fullwaveform inversion of shortoffset, bandlimited seismic. Pdf from the pdf of the available control points by a kriging technique.

Seismic inversion is a technique that has been in use by geophysicists for almost forty years. Inherently, seismic data is missing low frequency data which must be supplied by other means for the algorithm to work. Low frequency modeling and its impact on seismic inversion data. Seismic inversion and the importance of low frequencies kris innanen and gary margrave abstract crewes has made a signi. Interpreting bandlimited elastic ip, is volumes from prestack seismic inversion rafael r. Seismic inversion aims to reconstruct a quantitative model of the earth subsurface, by solving an inverse problem based on seismic measurements. Understand bandlimited impedance and how it can be used. In a seismic inversion the original reflectivity data, as typically recorded routinely, is converted from an interface property i. The elastic parameters themselves can be directly constrained during the seismic inversion and rockphysics relationships can be applied, constraining pairs of elastic parameters to each other.

Pdf this paper describes a seismic inversion method which has been cast as a matlab algorithm called blimp band limited impedance. Examples from mexico, egypt, australia and the north sea demonstrate applications of inversion. Seismic inversion process seismic inversion attempts to remove the effect of the wavelet and return the actual earth model 1. Using seismic inversion and net pay to calibrate eagle. Understand different approaches to seismic inversion and the role of the prior. Wellto seismic tie wavelet estimation a good tie correlation coefficient between the real and synthetic seismic trace greater than 85%, is necessary to estimate the wavelet properly. Bandlimited inversion trend model merged ai tie tie sena, 1997 castagna lecture note. This paper describes a seismic inversion method which has been cast as a matlab algorithm called blimp band limited impedance.

After an introduction to the uses of inversion, we present its various types, from simple to more complex. Final elasticparameter models optimally reproduce the input seismic, as this is part of the seismic inversion optimization. Seismic inversion is a method that extracts acoustic impedance data from the. Jul 14, 2006 2012 biobjective optimization for the inversion of seismic reflection data. Modelbased mbi, colored ci, sparsespike ssi, and bandlimited bli inversions are applied to the poststack seismic data from the blackfoot field. New insights for cbm reservoir modelling on muara enim formation, south sumatra faris mohamad noor and agra adipta. It can be used to invert seismic data using a well log, or some. Operto2 abstract fullwaveform inversion fwi is a challenging data. Seismic imaging and inversion application of linear inverse theory extracting information from seismic data requires knowledge of seismic wave. A simple algorithm for bandlimited impedance inversion crewes. Since the source wavelet is bandlimited and does not cover all frequencies, low and. Band limited and colour inversion are not recursive. Mathematics of multidimensional seismic imaging, migration. Persamaan rekursif diterapkan pada seismic trace gambar 3 3.

The use of l1 penalty in similar problems promotes sparsity of the solution rm 1. Seismic inversion and avo part 2 poststack inversion 22 introduction inversion is the process of extracting, from seismic data, the underlying geology which gave rise to that seismic. Seismic inversion and synthetic sonic logs calibration of seismic attributes to ground truth is still an emerging science. If it has to be carried out in depth, there are a few questions that come to mind what is so different about carrying out inversion in depth rather than time, how does it help, and if it were. Whether it is deterministic, bandlimited, or stochastic, seismic inversion can bear many names depending on the algorithm used to produce it. Acoustic impedance inversion can easily be computed by a standard impedance inversion algorithm which uses well logs to fill in the lowfrequency information that is missing in bandlimited seismic data. In stochastic inversion, the vertical variogram model controls the high frequencies. Seismic inversionmethodsacasestudyfromblackfootfield,canada. The seismic wavelet was assumed to be eliminated using deconvolution methods, so we have the reflectivity section with. This intermediate trend 212 hz separates out itself. The seismic data is bandlimited, it lacks the low frequencies that.

Low frequency modeling and its impact on seismic inversion. It handles a large range of seismic data in dedicated workflows from data conditioning to quantitative property estimation. Impedance inversion algorithm crewes research report volume 8 1996 211 a simple algorithm for bandlimited impedance inversion robert j. There are also numerous other impedance methods used in avo, such as the elastic impedance ei and extended.

Pdf poststack inversion transforms a single seismic data volume into acoustic impedance through integration of seismic data and well data. Prestack inversion is often used when poststack inversion fails to sufficiently differentiate geologic features with similar pimpedance signatures. Fullwaveform inversion of shortoffset, bandlimited seismic data in. Tahap processing bandlimited inversion hampson russell manual, 2006. In this study, we estimated the absolute ai with the given background ai and the bandlimited reflection profile, which was assumed to be multiplefree, amplitudecorrected and migrated after some processing and inversion steps. Initial background model berasal dari hasil filtrasi log impedansi pada well gambar 2 2. The seismic interpreter can interpret elastic inversion results without indepth knowledge about rock physics theory. Hardconstrain, bandlimited, and sparsespike seismic inversion. An overview of fullwaveform inversion in exploration geophysics. Seismic inversion methods and some of their constraints. While more sophisticated impedance algorithms exist, simple acoustic bandlimited impedance inversion is very quick and accessible. Pdf a simple algorithm for bandlimited impedance inversion. For all inversion methods, the prior model is constructed by interpolating filtered logs, and controls low frequencies.

Pdf seismic inversion methods and some of their constraints. Crains petrophysical handbook seismic inversion basics. Poststack inversion methods include sparse spike inversion, modelbased. Comparison of post stack seismic inversion methods. Seismic deconvolution using sparse spike inversion vs. From poststack inversion, the outcome is usually acoustic impedance, whereas prestack inversion may result. Early inversion techniques transformed the seismic data into pimpedance the product of density and pwave velocity, from which we were able to make predictions about lithology and porosity.

However, as seismic reflection data are naturally bandlimited, any inversion scheme depends upon an initial model, and must deal with non. Using seismic inversion and net pay to calibrate eagle ford shale producible resources bo chen 1, dhananjay kumar, anthony uerling2, sheryl land2, omar aguirre2, tao jiang1, and setiawardono sugianto1 1bp america, 501 westlake park blvd. Additionally, estimation of reflectivity from seismic data is always bandlimited and affects acoustic. Thus, seismic inversion can be a valuable tool for reservoir characterization prior to field development. Comparing geostatistical seismic inversion based on spectral. Using seismic inversion and net pay to calibrate eagle ford. There are two main types of inversion currently being used. Patrick connolly, pca ltd geophysics for integration. Broadly, inversion converts reflectivity data to physical properties of the earth, such as acoustic impedance ai, the product of seismic velocity and bulk density. Poststack inversion methods generally refer to the various workflows used to transform stacked seismic data into quantitative rock physics parameters. Workshop on geophysical data analysis and assimilation andreas fichtner 29 october 3 november, 2012 department of earth sciences, swiss federal institute of technology eth, zurich switzerland department of earth sciences, utrecht university utrecht the netherlands full seismic waveform modelling and inversion. The black traces in a correspond to the actual seismic. In fact all seismic method pre or post stack, deterministic or sthocastic are recursive. This study developed out of a need to better understand the significance of seismic amplitude variations over the crest of lavrans field figure 2.

A comparison between model base hardconstrain, bandlimited. Appreciate the role of the gradient in the determination of vpvs from seismic inversion. Removing the background trend from the data would reveal out the anomalous geobodies. From poststack inversion, the outcome is usually acoustic impedance, whereas prestack inversion may result in both acoustic impedance and shear impedance. There are at least three fundamental issues to be solved simultaneously. On the right side, we introduce geological constraints taken from a sonic log or seismic velocity information and produce a forward model. Stochastic vs deterministic pre stack inversion methods. We present a highresolution pwave velocity model of the sedimentary cover and the uppermost basement to. Poststack seismic inversion, developed in the 1970s, reverses the forward. Modelbased inversion, colored inversion, sparsespike inversion, bandlimited impedance inversion. Seismic inversion and the importance of low frequencies. The seismic traces in the stacked seismic section shown in figure 2 can be modelled as the convolution of the earths reflectivity and a bandlimited seismic wavelet, which can be written. Acoustic and elastic impedance models of gullfaks field by poststack seismic inversion.