Model based seismic inversion software

Appraise the various methods of seismic inversion and their value to interpretation, including model based methods, structural deconvolution and relative acoustic impedance. The software described in this paper is a tracebased inversion routine, and is designed to draw stochastic samples from the posterior distribution of. The second approach is modelbased inversion technique russell and hampson, 1991. Seismic reservoir characterization reservoir software cgg. Modelbased inversion russell and hampson, 1991 uses a generalized linear inversion algorithm.

This research challenges the notion that the seismic inversion, as a onetoone mapping for the beg survey, can produce a usable geologic model. Seismic inversion can be formulated as a mathematical optimization problem that minimizes the difference between field recorded data and numerically modeled synthetic data. A model typically has a vertical cell resolution of 1m, but seismic inversion is more typically a vertical resolution of 20m. In a modelbased inversion, a simple initial acoustic impedance. A possible workflow for performing a modelbased seismic inversion consists of loading three types of data. Interwell is a seismic inversion and characterization software for reservoir and exploration geophysicists. Estimation of impedance using seismic reflection data. Compare inversion methodologies and results with the wider family of seismic attributes. Full supporting systems for model based avo and seismic inversion minimize data handoff errors.

The result is a structured model that best fits raw data. Removing the background trend from the data would reveal out the anomalous geobodies. In this brief summary of inversion methods, we have considered two different approaches. Post stack inversion of the hussar low frequency seismic data. Full waveform inversion fwi is nonlinear datafitting procedure that aims at obtaining detailed estimates of subsurface properties from seismic data, which can be the result of either passive or active seismic experiments.

The aim of this paper is rather to introduce a new opensource software tool delivery for bayesian seismic inversion, and demonstrate how this code implements a modelbased bayesian approach to the inversion problem. Modelbased seismic inversion, sequential gaussian simulation with cokriging for porosity modeling, and truncated gaussian simulation with trend for facies modeling were used to characterize the. Appraise the various methods of seismic inversion and their value to interpretation, including modelbased methods, structural deconvolution and relative acoustic impedance. Low frequency modeling and its impact on seismic inversion. The viewpoint and experience base of the authors at least the first author is that of a consumer of seismic inversion as opposed to a provider of inversion software. Earthworks seismic inversion plugin for decisionspace. The aim of this paper is rather to introduce a new opensource software tool delivery for bayesian seismic inversion, and demonstrate how this code implements a model based bayesian approach to the inversion problem. These methods minimize an objective function, which is usually a measure.

The software described in this paper is a tracebased inversion routine, and is designed to draw stochastic samples. Given an initial guess of the subsurface parameters, a model the data are predicted by solving a waveequation. The inversion process can be applied to poststack or prestack data. Model based seismic inversion, sequential gaussian simulation with cokriging for porosity modeling, and truncated gaussian simulation with trend for facies modeling were used to characterize the. While seismic exploration remains the primary method of exploring for petroleum, use of gravity and magnetic modelling methods has continued to expand, based on their contribution to reliable evaluations and recent discoveries in deeper, more challenging environments such. The input to seismic modeling is a representation of the earths reflectivity and a velocitydepth model. In this dissertation, i apply a sampling technique called reversible jump markov chain monte carlo rjmcmc to traverse the model space. Seismic reservoir characterization using model based. Stochastic and deterministic seismic inversion methods for.

Seismic is able to link a large number of documents types that are easily updated, and the data is also backed up securely to the cloud. A comprehensive suite of migrations, including full wave, kirchhoff and local angle domain migrations, can be applied to solve a broad range of imaging. We reserve the term model based inversion for methods that attempt to achieve resolution within and beyond the seismic band by a stronger use of the a priori impedance logs in the model term of equation 1. This functional relationship is some mathematical model derived from the fundamental laws of physics and is more often called a forward model. Poststack model based inversion most geophysicists find it more intuitive to interpret seismic data in terms of impedance rather than reflectivity. Three wells located close to the seismic line and a dynamitesource dataset, acquired with threecomponent 10 hz geophones, were used for a poststack inversion test using commercial software.

Based on a petroelastic model pem, petrophysical inversion simultaneously integrates all subsurface information to provide reliable, quantitative, fine scale descriptions of reservoir properties. An overview of techniques used in the inversion of seismic data is provided. We reserve the term modelbased inversion for methods that attempt to achieve resolution within and beyond the seismic band by a stronger use of the a priori impedance logs in the model term of equation 1. The prior model in delivery is a tracelocal layer stack, with rock physics information taken. Poststack model based inversion makes this possible. Seismic modelbased inversion using matlab intechopen. Waveform inversion is a powerful and computationally expensive method for estimating an objects material properties and imaging its internal structure virieux and optero, 2009, burstedde and ghattas, 2009. Modeling for inversion in exploration geophysics seismic. The software described in this paper is a trace based inversion routine, and is designed to draw stochastic samples from the. Inseis utilises a model driven inversion to provide you with a solution which is independent of the starting model, with good wellto. The deterministic nature of linear inversion requires a functional relationship which models, in terms of the earth model parameters, the seismic variable to be inverted. We introduce a new opensource toolkit for model based bayesian seismic inversion called delivery.

Integrating seismic acoustic impedance inversion and attributes for. We state that the inversion process is modeldriven because the observed seismic data can be considered as a forward model in which the seismic wavelet is convolved with the earths reflectivity series. In other words, seismic attributes at a specific time may represent the convolution of the desired reservoir element with neighboring layers e. Reservoir characterization using model based inversion and.

We allow for uncertainty in both the fluid type and saturation in. With a probabilistic modelbased inversion, all acceptable earth impedance models are output. A considerable advantage together with the outstanding features are the integrations, and the highly flexible quotebased pricing which makes seismic accessible even to small businesses and startups. Seismic inversion the best tool for reservoir characterization. Modelbased seismic acoustic impedance inversion method and attribute.

The process starts with an initial model based on a conventional raytracing tomography. With a probabilistic model based inversion, all acceptable earth impedance models are output. The aim of seismic inversion is specifically to transform the conventional seismic reflection responses into a layered model representation that distinguishes different formations. Seismic migration is a process of estimating earths reflectivity from a recorded seismic wavefield using a velocitydepth model. Citeseerx document details isaac councill, lee giles, pradeep teregowda.

Pdf seismic reservoir characterization using model based. Therefore, seismic wavefield modeling may be viewed as the reverse process of seismic migration. Inseis utilises a model driven inversion to provide you with a solution which is independent of the starting model, with good welltoseismic ties, allowing for. Model based inversion produces a blocky output that contains more geological detail than bandlimited inversion. A possible workflow for performing a model based seismic inversion consists of loading three types of data. Estimation of impedance using seismic reflection data based. Fullwaveform inversion seismic laboratory for imaging. This method models the subsurface as layers or blocks in terms of acoustic impedance and time. The process of solving this optimization problem then requires to numerically model, thousands of times, wavepropagation in large threedimensional representations of part. Equipoise software produces the kingdom seismic inversion module for ihs markit kingdom. Full waveform inversion fwi is a recent exciting technique for the seismic industry because of its potential to deliver very detailed subsurface imaging. Colored inversion a matching filter is designed and the seismic traces are processed to match the coloration of the acoustic log data. The prior model in delivery is a tracelocal layer stack, with rock physics information taken from log analysis and layer times initialised from picks. This flexible piece of seismic inversion software allows the petroleum geologist to use multiple means of identifying and categorising data to better fit the project at hand.

A comprehensive suite of migrations, including full wave, kirchhoff and local angle domain migrations, can be applied to solve a broad range of imaging objectives, such as thrust fault, subsalt and rugged terrain imaging, and accommodate a. Poststacked 3d seismic data, composite well logs, and velocity checkshot data were used for the reservoir analysis. Without an inversion software, results are very difficult to evaluate. The work flow illustrated in this poster will be for poststack data seismic inversion. Prestack inversion outline 1 prestack inversion 2 full waveform inversion the basic idea 3 the math 4 marmousi example estimating the initial model fwi bee bednar panorama technologies seismic modeling, migration and velocity inversion may 30, 2014 3 53.

Stochastic, modelbased seismic inversion is a widely used global optimization technique and markov chain monte carlo mcmc method is a natural choice to sample model parameters during the random walk. Stochastic inversion, and doubledifference waveform inversion, and fullwaveform ambient noise inversion, for example, could all be implemented in this manner. In the study, model based poststack inversion technique was used to create pseudo logs at each seismic trace at the well location to constitute high resolution acoustic inverted impedance models. Inversion is defined as mapping the physical structure and properties of the subsurface of the earth using measurements made on the surface, creating a model of the earth using seismic data as input. This generates reservoir models with geologicallyplausible shapes, and provides a clear quantification of uncertainty to assess risk. Generally, the stochastic inversion methods use broadband starting models drawn from welllogbased a priori distribution of the model space and apply a globalsearch method for seismicdata fitting torresverdin et al1999, francis 2006a, 2006b, srivastava and sen 2010. Pdf in the study, model based poststack inversion technique was used to create. Introduction to seismic inversion in paradigm youtube. Models can be one, two, or three dimensional and consist of depth horizons and associated p wave velocities, s wave velocities, and densities. Poststack modelbased inversion most geophysicists find it more intuitive to interpret seismic data in terms of impedance rather than reflectivity.

Structural interpretation and inversion analysis were used to characterize hardtoimage reservoirs, to predict subsurface interwell reservoir properties for optimum reservoir heterogeneity description, and to finetune drilling locations in dj field, niger delta. We allow for uncertainty in both the fluid type and saturation in reservoir layers. Finally, in addition to carrying out inversions and migrations, users can script entirely new workflows by invoking the solver, preprocessing, postprocessing, and nonlinear optimization. This process can be considered to place in either stochastic or deterministic space. Seismic modelbased inversion using matlab, matlab modelling, programming and simulations, emilson pereira leite, intechopen, doi. A deterministic modelbased inversion will output just one earth impedance model that fits the seismic data being inverted, and the user of that deterministic inversion has a risk of being proven wrong by the drill bit. Pdf seismic reservoir characterization using model based post. Integrating seismic acoustic impedance inversion and. A deterministic model based inversion will output just one earth impedance model that fits the seismic data being inverted, and the user of that deterministic inversion has a risk of being proven wrong by the drill bit. We have introduced one more category as the intermediate trend.

Apr 25, 2016 seismic inversion is an important tool in reservoir characterization that enables you to combine well and seismic information to predict lithology and fluid content. Structural interpretation and inversion analysis were used to characterize. Image size 2000 px notice that very large and arbitrary shaped domains can be mapped. You can explore the effect of this geophysical uncertainty on. Interwell is a seismic inversion and characterization software for reservoir and exploration geophysicists, available in linux and windows environments. Modelbased inversion of broadband seismic data crewes. The job of an inversion model is to calculate the true resistivity distribution from all apparent resistivities. The software described in this paper is a tracebased inversion routine, and is designed to draw stochastic samples from the. Facilitates inversion of both prestack and poststack seismic to produce impedance attribute volumes provides easy qc and inversion parameter optimization at well locations using inversion analysis enables access to multiple inversion techniques such as modelbased, colored and. Pdf application of modelbased inversion technique in a. Modelbased inversion of lowfrequency seismic data earthdoc.

Stochastic, model based seismic inversion is a widely used global optimization technique and markov chain monte carlo mcmc method is a natural choice to sample model parameters during the random walk. Ultrafast stochastic inversion software builds upon your modelbased deterministic solution provided with this release by allowing you to understand the uncertainty inherent in seismic inversion. Interwell seismic inversion and reservoir characterization. The specific software used in this research to perform model based inversion of stacked seismic data is hr hampsonrussell strata program by cgg. Geostatistical inversion integrates high resolution well data with low resolution 3d seismic, and provides a model with high vertical detail near and away from well control. Please contact your local ihs sales team for a trial of seismic inversion as part of the ihs kingdom software package seismic inversion is also available as a component of the equipoise software inseis package the model parameters to be determined are the formation properties. Low frequency modeling and its impact on seismic inversion data. I s is the 1d numerically simulated synthetic seismic data variables with low superscripts designate lowfrequency components of. The process of imaging through modeling the velocity structure is a form of inversion of seismic data, and the term inversion is often used to imply building a velocity model which is iteratively improved until it and the seismic data are optimally in agreement. We introduce a new opensource toolkit for modelbased bayesian seismic inversion called delivery. Earthworks seismic inversion plugin for decisionspace version 5000. Seismic inversion a work flow for modelbased inversion.

Whether applied to a human body, a hydrocarbon reservoir, or a continental craton, careful integration of software components, including waveequation solvers, nonlinear. Comparison of post stack seismic inversion methods. Use our software to produce detailed models of reservoir character. The hussar experiment was carried out in central alberta, canada, in september 2011 with the purpose of acquiring low frequency seismic data to be used in inversion methods. Geodepth is designed to easily handle the full range of global seismic imaging challenges.

This research challenges the notion that the seismic inversion, as a onetoone mapping for the beg survey, can produce a usable geologicmodel. In one of the model driven methods we support, the simplicity term is implemented by limiting the solution. Seismic inversion is an important tool in reservoir characterization that enables you to combine well and seismic information to predict lithology. The first is bandlimited inversion, in which a scaled relative impedance from the seismic data is mixed with a low frequency element from the model.

Interwell seismic inversion and reservoir characterization beicip. First, a zerophase estimate is determined and applied to the data. Facilitates inversion of both prestack and poststack seismic to produce impedance attribute volumes provides easy qc and inversion parameter optimization at well locations using inversion analysis enables access to multiple inversion techniques such as model based, colored and sparse spike inversion algorithms. Well log data are used to tie the main time horizons to the seismic data and define the impedance bounds for each model layer. Modelbased inversion, colored inversion, sparsespike inversion, bandlimited impedance. Fullwaveform inversion seismic laboratory for imaging and. Marmousi inversion seismic 2 model the industry standard marmousi model was used as a test case, to validate our models ability to generalise for geometries that it has not seen before. Model based inversion russell and hampson, 1991 uses a generalized linear inversion algorithm which assumes that the seismic trace s and the wavelet w are known and attempts to modify the initial model until the resulting synthetic matches the seismic trace cooke and schneider, 1983. Poststack modelbased inversion makes this possible.

Forward numerical modeling of seismic data is the use of geological models of the earth to simulate seismic field experiments. Seismic to simulation software and hampsonrussell inversion software. Ultrafast stochastic inversion software builds upon your. Low frequency modeling and its impact on seismic inversion data any deviation from this shale trend is an anomalous signature. Full supporting systems for modelbased avo and seismic inversion minimize data handoff errors.

This intermediate trend 212 hz separates out itself. Select the inversion methods for your particular analysis, based on project workflow. The second approach is model based inversion technique russell and hampson, 1991. It uses generative adversarial networks gans, to map between velocity and the seismic domain in both directions.

The starting model is defined by a few 3d main time horizons. Seisflowsflexible waveform inversion software sciencedirect. Bandlimited inversion is a robust method that produces a smooth and continuous output. Generally, the stochastic inversion methods use broadband starting models drawn from welllog based a priori distribution of the model space and apply a globalsearch method for seismic data fitting torresverdin et al1999, francis 2006a, 2006b, srivastava and sen 2010. It provides a direct link between seismic data and reservoir modeling, as it is applied on a geocellular model filled with rock properties in depth. Modelbased inversion produces a blocky output that contains more geological detail than bandlimited inversion. A second problem with using seismic inversion data in reservoir modeling is the large difference in vertical resolution between the model and the seismic impedance.