Prestack seismic interpretation pdf

If the seismic workflow is roughly acquisition processing interpretation analysis, then impedance and elastic inversion are in the analysis part of the seismic workflow. Case study in the hoop area, barents sea, norway pedro alvarez, amanda alvarez, lucy macgregor, francisco bolivar, robert keirstead, and thomas martin. In 1997, he founded 3dsymsam geophysical advice, focusing on 3d seismic survey design and analysis. Our prestack pro software combines prestack visualization, processing, and interpretation in one powerful platform. Pdf attributes assisted seismic interpretation in prestack time. The second case is an example of elastic model building casting prestack seismic inversion as a machine learning regression problem. The integration of early quantitative seismic interpretation qsi into the seismic interpretation process is one of the most effective methods for reducing uncertainty in the long term. This article describes the science and art of seismic inversion, and how oil and gas companies are using it to reduce risk in their exploration. Prestack time migration pstm has pitfalls in processing seismic data, which causes artificial features on seismic images and might mislead. Paradigm qsi provides the tools needed to derive information about rock type, lithology, reservoir properties, fluid fill, elastic properties, and geomechanical properties, for a better assessment of drilling success probability.

Petrel prestack seismic interpretation plugin schlumberger. Download pdf info publication number us20090037114a1. With a common data format for pre and poststack seismic data, coupled with onthefly conversion of trace files to efficient brick structures for data roaming, paradigm has overcome the traditional barriers associated with the use of prestack data in an interpretation and analysis environment. Normal moveout nmo and stacking of csp gathers is performed to complete the prestack migration process. A method of prestack time migration based on the principles of prestack kirchhoff time migration that can be applied to both 2d and 3d data. Feb 07, 2016 the success of a quantitative seismic interpretation project requires highquality prestack seismic data. We describe a new workflow that gives geophysicists and geologists more flexibility in checking the quality of prestack seismic data and helps them select the best angle stacks for amplitude and structural. In prestack inversion, in addition to the pwave acoustic impedance, shear impedance and density can be extracted from prestack seismic data. Pdf prestack time migration pstm has pitfalls in processing seismic data, which causes artificial features on seismic images and might.

Pdf the dataset generated in prestack seismic processing consists of a variety of attributes and cmp gathers. Seismic attributes, especially coherence and curvature, often exacerbate the effect of. The authors provide an integrated methodology and practical tools for quantitative interpretation, uncertainty assessment, and characterization of subsurface. The dtsm log is a very important log because it helps us determine k and k c correctly. Summary over the last decade, it is predominantly perceived that there have been significant evolutions in prestack depth imaging. The success of a quantitative seismic interpretation project requires highquality prestack seismic data. Seismic attributes, seismic geomorphology, local structural dip 1. Summary recent advances in software development have enabled seamless use of prestack seismic data combined with advanced attributes and highend interpretation and visualization workflows.

Final elasticparameter models optimally reproduce the input seismic, as this is part of the seismic inversion optimization. Virtually all seismic data processing is aimed at imaging the earths subsurface, that is, obtaining a picture of subsurface structure from the seismic waves recorded at the earths surface. The ovtdomain wideazimuth prestack seismic interpretation technology is composed of five key prestack analysis and interpretation techniques focused on ovt gathers. Prestack depth migration an ultimate aspiration for subsurface imaging in geologically complex area. Marfurt abstract we compare the effect of 3d poststack versus 3d prestack imaging on seismic coherence, seismic amplitude, and seismic amplitude variation.

Most seismic data is processed to optimize image quality for structural and stratigraphic interpretation, with little regard to preserving characteristics essential for successful seismic reservoir characterization. Benefits of analyzing prestack seismic data combined with. Poststack, prestack, and joint inversion of p and swave. I just wanted to explain again a bit, hoping it might help if the op hears it several different ways. I guess a footnote to the prestack vs poststack question is that sometimes you want to interpret the. Prestack seismic interpretation poised to go mainstream at statoil. Introduction recent development of threedimensional 3d seismic datasets enables geologists to visualize and analyze buriedlands and seascapes revealed by subsurface geophysical. Seismic inversion is essentially a very simple procedure.

The inversion is usually strongly constrained by well logs, when they are available. An acquisition footprint can obstruct not only classical seismic interpretation but it can also affect interpretation based on seismic attributes marfurt et al. Common scatter point csp gathers are created as an intermediate step for each output migrated trace. The impact of interbed multiples on the inversion and interpretation of prestack data.

Controlled stacking for improved quality of prestack depth. The importance of effective prestack data qc and evaluation cannot be overemphasized. This specialized set of applications within hampsonrussell improves the signaltonoise ratio and alignment of cdp gather data in preparation for any prestack analysis process such as avo or simultaneous inversion. 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. Abstractin this tutorial, i present an overview of the techniques that are in use for prestack seismic amplitude analysis, current and historical. In a seismic inversion the original reflectivity data, as typically recorded routinely, is converted from an interface property i.

But what makes prestack seismic data particularly important is that they open our understanding in the. Pdf combining rock physics analysis, full waveform prestack. Inversion in general means youre trying to get at velocity andor density or their product, impedance, from the recorded seismic data. This process, called seismic inversion for reservoir characterization, can help fill gaps in our knowledge of formation properties between wells. Offset vector tile domain wideazimuth prestack seismic. Prestack seismic data is applied routinely in the process of quantitative seismic interpretation qsi to generate varieties of seismic attributes, in order to estimate reservoir properties such. We analyzed the generated synthetics using seismic attributes for the different hypotheses to decide which is most likely. Sensitivity, calibration, and application gee shang pan, chi. A cnn is trained to make predictions of 1d velocity and. I get the math but dont understand the physical idea behind them. Pdf threeparameter prestack seismic inversion based on l 1. To understand the distinction between impedance and reflectivity, refer to figure 1, which shows the different ways in. Comprehensive seismic data analysis and interpretation.

Migrating the data, moves reflections to their correct spots. Pdf threeparameter prestack seismic inversion based on. The petrel prestack seismic interpretation plugin enables prestack seismic visualization, interpretation, and interactive processing to bridge the gap between prestack and poststack interpretation workflows. In the case of carbonate sulfur deposits, seismic interpretation is mainly. Use of prestack depth migration for improving the accuracy. A complete processing flow for vertical and both horizontal components was conducted to obtain stacks and prestack gathers with preserved. Seismic reservoir characterization of duvernay shale with quantitative interpretation and induced seismicity considerations a case study satinder chopra, ritesh kumar sharma, amit kumar ray, hossein nemati, ray morin, brian schulte, and david damico. Most seismic data is processed to optimize image quality for structural and stratigraphic interpretation, with little regard to preserving. Most seismic surveys provide images using data that have been stacked. Final elasticparameter models optimally reproduce the input seismic, as.

The swave velocity contrast between the morrow shale and a sandstone is strong compared with the pwave velocity contrast, and, therefore, multicomponent seismic data could help to characterize these reservoirs. Prestack inversion transforms seismic angle or offset data into pimpedance, simpedance and density volumes through integration of the seismic angleoffset gathers, well data and a basic stratigraphic interpretation. Other combinations of elastic parameters such as pimpedance, vpvs ratio and density are equally possible. Reservoir properties prediction integrating controlledsource electromagnetic, prestack seismic, and welllog data using a rockphysics framework. Bancroft published in the cseg recorder november 2001 abstract the kinematics of prestack data considers an arbitrary offset between the source and receiver. Gather conditioning removes noise, provides consistent fold, timealigns reflection events and can. Seismic data gather conditioning for prestack seismic data inversion.

A successful seismicbased reservoir properties estimation effort has three steps. An integrated targetorientedprestack elastic waveform inversion. Controlled stacking for improved quality of prestack depthmigration results david kessler, cgg american services, houston, texas luis canales and chungchi shih, cogniseis development, houston, texas peter duncan, 3dx technologies, houston, texas d epth migration of seismic data is becoming more routine for imaging of complex geological. The effect of 3d prestack seismic migration on seismic.

Also how how does prepost stacking affect our interpretation of the seismic data. In addition to authoring 3d seismic survey design 2002, 2012, vermeer has written seismic wavefield sampling 1990, both published by seg. At present, the critical issue in the application of seismic inversion is the estimation of elastic parameters in the thin. Gc prestack impedance inversion aids interpretation.

This specialized set of applications within hampsonrussell improves the signaltonoise ratio and alignment of cdp gather data in preparation for any prestack analysis process such as avo or simultaneous inversion improve gather data for prestack analysis. The impact of interbed multiples on the inversion and. Pdf attributes assisted seismic interpretation in pre. Practical seismic interpretation pdf free download. Thewhich in this case is prestack impedance inversion.

Unmigrated is wrong because there are inherent velocity assumptions which makes the image incorrect. The hanging wall is the only oil productive block with area coverage of 5x3 km and consists of 129 producers and 24. Poststack, prestack, and joint inversion of p and swave data for morrow a sandstone characterization paritosh singh. Controlled stacking for improved quality of prestack depthmigration results david kessler, cgg american services, houston, texas luis canales and chungchi shih, cogniseis development, houston, texas peter duncan, 3dx technologies, houston, texas d epth migration of seismic data is becoming more routine for imaging. Disturbances initiated by a seismic energy source are assumed to propagate in accordance with solutions to the wave equation. Pdf prestack seismic data analysis with 3d visualization a.

Inversion and interpretation of seismicderived rock properties in the duvernay play interpretation. Seismicderived elastic properties may be used to help evaluate hydrocarbon production capacity in unconventional plays such as tight or shale gas. Prestack time migrated pstm data are routinely used for interpretation, prospect generation, and well planning of unconventional plays. Application of crossplot and prestack seismicbased impedance. Attributes assisted seismic interpretation in prestack time versus depth migration dat a tengfei lin 1, hang deng 1, zhifa zhan 2, zhonghong wan 2, and kurt marfurt 1 search and discovery. A successful seismic based reservoir properties estimation effort has three steps. An integrated targetorientedprestack elastic waveform. Simultaneous inversion of shallow seismic data for imaging.

Efficient management of prestack seismic data landmark solutions. Furthermore, with using this log the initial models of swave velocity and shear impedance are more accurate. Motivations for automated salt top extraction is a growing. Prestack visualization and analysis for quantitative seismic. A unified 2d land seismic data analysis workflow oz yilmaz, geotomo, houston, describes a timewithdepth workflow for earth modelling and imaging in areas with irregular topography, complex nearsurface, and complex subsurface based on analysis of seismic data in shotreceiver coordinates, not in midpointoffset coordinates. Organic content and maturation effects on elastic properties of source rock shales in the. Comprehensive seismic data analysis and interpretation with. Prestack depth migration an ultimate aspiration for. Attributes assisted seismic interpretation in prestack time versus. Seismic facies analysis from prestack data using selforganizing maps. Heres a thing i wrote on the subject when people talk about poststack inversion they are usually talking about recovering.

Big aid in interpretation h aving first examined the poststack and prestack methods of seismic impedance inversion may and june 2015 explorer, we now end the threepart series by turning our attention to joint inversion of multicomponent data. 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. Different between poststackprestack seismic inversion. Another element to the text is a set of twenty relatively short questions with answers that will prove useful to teachers who are pressed for time to carry out a full seismic survey interpretation exercise. Psi complements existing 3d volume interpretation workflows by allowing interpreters access to the wealth of information contained in prestack data. Pdf combining rock physics analysis, full waveform. Prestack, and poststack migration refer to different points in the processing flow at which you decided to migrate the data.

Prestack crewes research report volume 2001 555 cos rms stk v v. Gc prestack impedance inversion aids interpretation satinder chopra. Solution to derive the maximum benefit of prestack seismic, data access and analysis capabilities need to be placed in the hands of everyday interpreters. Improved seismic interpretation of a salt diapir by utilization of diffractions, exemplified by 2d reflection seismics, danish sector of the north sea mahboubeh montazeri, lars ole boldreel, anette uldall, and lars nielsen.

Quantitative seismic interpretation demonstrates how rock physics can be applied to predict reservoir parameters, such as lithologies and pore fluids, from seismically derived attributes. Rahayu field was discovered in 1973 and it is a threeway closure anticline bounded by thrust fault bearing nwse at the west. Exploration for oilbearing morrow sandstones using conventional seismic datamethods has a startlingly low success rate of only 3%. However, although a 3d psdm seismic volume was used for interpretation, it was generated from a decimated input data set, which is a costquality tradeoff routinely adopted in the velocity model building stage of. Therefore, the main aim of this study is to use crossplot analysis and seismic simultaneous inversionderived poisson impedance to discriminate. Characterization of a shalegas reservoir based on a seismic amplitude variation with offset inversion for transverse isotropy with vertical axis of symmetry media and quantitative seismic interpretation. Interpretation of geologic facies in seismic volume using key rock elastic properties and highdefinition facies templates mahbub alam, sabita makoonsingh, joan embleton, david gray, and larry lines. Prestack event interpretation uses a true 4d tracker, seeded from gather picks and horizons. The goal of this work is to demonstrate the detection and extraction of salt tops from seismic data via the application of deep learning.

By combining prestack seismic and well log data, inversionbased volumes of elastic properties may be produced. Prestack impedance inversion aids interpretation, by. Seismic attributes and their applications in seismic. Delineation of karsts, a new approach using seismic. Reading between the lines frazer barclay perth, western australia, australia. Seismic facies classification has become a stan dard technique used in interpreting 3d seismic data volumes. The effect of 3d prestack seismic migration on seismic coherence and amplitude variability walter e. The added dimension of the sourcereceiver offset defines a prestack. Oz yilmaz has expanded his original work on processing to include inversion and interpretation of seismic data. In order two basic approaches to ensure recorded seismic data conto reduce this undesired component of the seismic signal, we form to these assumptions might be termed velocitybasedassume that any noise remaining after conventional pro and staticsbased. Prestack impedance inversion aids interpretation, by satinder. Deconvolution, for example, aims to sharpen reflections, and common midpoint cmp stacking exploits data redundancy to enhance signaltonoise ratio while producing a seismic time section that simulates. Prestack inversion has become a common approach in reservoir prediction.