Advanced velocity modeling incorporate well log velocities, time depth curves, event and fault interpretation, and seismic velocities into a consistent velocity model. Practical depth conversion and depth imaging for the. Imageray tracing for joint 3d seismic velocity estimation and time to depth conversion. Simple being free of charge is not sufficientsee gratis versus libre. Oil and gas consultant scott mackay is an independent consultant with 35 years of experience. We work hard to earn and maintain your trust and, along with our technical staff, work with you247in solving your toughest seismic problems. To convert from time s to depth ft you must know the velocity of the material. An introduction to velocity modelling and depth conversion in. A well depth and a seismic horizon time to the same event can be used to define a socalled pseudovelocity and these are often used in depth conversion.
A seismic section consists of numerous traces with location given along the xaxis and twoway traveltime or depth along the yaxis. Shared advances in exploration and fundamental geophysics. Conversions within the same domain timetotime and depthtodepth can be used for flattening, avo, and 4d seismic workflows, as well as workflows calibrating prestack depth migration data to well markers. From regional exploration to reservoir development and production optimization, geophysics is a critical tool to solve the most complex structural and stratigraphic challengesincluding advanced seismic processing, depth imaging, and 3d, 2d, and prestack seismic interpretation as well as advanced quantitative interpretation. Volume 83, issue 3 3d forward modeling and inversion of electromagnetics and applications. Here we will go through a time to depth conversion of a 2d seismic survey in the sichuan basin using a velocity model provided in depth. Kingdom suite how to create timedepth chart in excel duration. Interpret a set of time horizons from an image volume derived from time migration. Gverse geophysics software is a powerful, fully integrated 2d and 3d seismic interpretation system that provides a full range of fitforpurpose interpretation capabilities, attribute analysis, and mapping tools. Due to the velocity structure, the high point on the depth section is at location e. Geophysics software, geophysical interpretation software. Geophysics a display of seismic data along a line, such a 2d seismic profile or a profile extracted from a volume of 3d seismic data. Timedepth conversion incorporated research institutions for.
Jan 07, 2019 depth conversion methods in terms of complexity, which means cost, time, detail and relative difficulty in implementing. Dix conversion still is the robust method for interval velocity. Through the integration of interpretation, velocity analysis, model building and updating, model validation, depth imaging, and timetodepth conversion, geodepth provides the continuity needed to produce highquality, interpretable images consistent with other available data, while preventing data loss and honoring geologic constraints. Vertical time to depth conversion advanced focus on data integration and vertical time to depth conversion. We hope that students will then be able to develop company specific workflows using what they have learned in the course. Learn the importance of looking at all of the data, including logs and seismic. In order to create a reservoir model or compute volumetrics, these time interpretations need to be converted to depth and calibrated to well markers. Seisware continues to be the seismic interpretation choice at encana. Notice that free and opensource requires that the source code is available. Kingdom seismic and geological interpretation software ihs. Seismic data is acquired in time the time taken for the sound to travel from the source to reflectors and to return to receivers. Kingdom seismic and geological interpretation software.
Geophysics kingdom geophysics software is the market leader for geophysical interpretation. These distinctions mark our executive, technical, and business team. Sonic velocities and depth conversion cseg recorder. Seismic velocities and depth conversion svdc may 28th, 2014 seismic data is acquired in time the time taken for the sound to travel from the source to reflectors and to return to receivers. A velocity model is required in the form of a voxet. A robust approach to time to depth conversion and interval velocity estimation from time migration in the presence of lateral velocity variationsa apublished in geophysical prospecting, 63, no. Distinguish between commonly used migration algorithms. Kingdom provides advanced geoscience including avo and attribute analysis, geosteering, microseismic interpretation, and time to depth velocity modeling to every interpreter not just the specialist. To convert time reflections to a depth surface we need to know the velocity. The timetodepth conversion strategy involves the following steps. He is an acknowledged expert in interpretation, depth conversion, and depth.
Ixseg2segy seismic record viewingprocessing utility format conversion, first break picking segy viewer, seg2 viewer shareware. Alan atkinson outline this is a course for practicing seismic interpreters tasked with creating depth maps for volumetrics and well planning. Depth conversion, ideally, is an iterative process that begins with proper seismic processing, seismic velocity analysis and study of well data to refine the conversion. The reader interested in freeware just free of charge software is referred to the list of freeware geophysics software. Timetodepth conversion and seismic velocity estimation. Comprehensive poststack velocity modeling for interpreters and depth conversion experts. Depth conversion integrates several sources of information about the subsurface velocity to derive a threedimensional velocity model. Conductivity depth imaging of helicopterborne tem data based on a pseudolayer halfspace model. The objective of this course is to expose students to as many tools as possible for performing time to depth conversion while giving examples of meaningful workflows. Learn how to optimally calibrate synthetic seismograms for use in depth conversion. Geophysics was one of four products we tested as part of the rfp. Seisware won the contract in july 2004 and continues to be the seismic interpretation choice at encana. A robust approach to timetodepth conversion and interval. Variations in velocity can distort the depth, size, and shape of possible reservoirs.
Through the integration of interpretation, velocity analysis, model building and updating, model validation, depth imaging. Approximating a seismic horizon timedepth conversion. The unconventional depth conversion method, shown in figure 3, involves velocity data extracted from processed, or raw, sonic log digital data or velocities extracted from check shot surveys, the integration of time domain data into the depth domain and the inclusion of a geologically contrived depth model. This is a case study and gives the practical approach for velocity modeling which can be further utilized for time to depth conversion. Kingdom suite how to create timedepth chart youtube. Dynamic depth conversion and map update dynamically build velocity models by tying your well and seismic data advanced velocity modeling incorporate well log velocities, timedepth curves, event and fault interpretation, and seismic velocities into a consistent velocity model. On the time section, the high point for the deepest horizon is at location d.
Only 3d local geostatistics combined with a geological expertise can feed a velocity model with high resolution 3d heterogeneities, thus leading to minimum depth errors. Hence, we use the dix velocity instead of timemigration velocity as a more convenient input. The velocity of a rock is a fundamental physical property related to its hardness. Approximating a seismic horizon timedepth conversion using a twovelocity layer approach in seisworks frequently in industry you will want to display a horizon map in depth ft instead of the landmark seisworks default, which is twoway time twt. Velocity can be determined from laboratory measurements, acoustic logs, vertical seismic. Geodepth reduce drilling risk through advanced velocity determination, modeling, and imaging. Depth conversion is an important step of the seismic reflection method, which converts the acoustic wave travel time to actual depth, based on the acoustic velocity of subsurface medium sediments, rocks, water depth conversion integrates several sources of information about the subsurface velocity to derive a threedimensional velocity model. Synthetic seismograms and time depth relationships. Explorationists rely on the paradigm geodepth velocity determination and 3d2d velocity model building system to create accurate seismic imaging in either time or depth. Acoustic logs, checkshot surveys and vertical seismic profiles can aid depth conversion efforts and improve correlation of well logs and drilling data with surface seismic data. Switch to depth mode in time interpretations and convert entire time scenes to depth onthefly.
Gverse geophysics software is a fully integrated 2d and 3d seismic interpretation system that provides a full range of fitforpurpose interpretation capabilities, attribute analysis and mapping tools. Encana was tasked with migrating geoscientists to a pc based software platform. The depth conversion can now be carried out as part of the data processing, but this depth imaging is only done in special circumstances. Ixseg2segy is a 32bit windows program designed to read seg1, seg2, segy, ascii, csv and other instrument manufacturers multichannel seismic data formats, view, process and interpret the data using simple techniques and output the data as seg2, segy or. This is the main takeaway from this lesson that time structure is not always the same as depth structure. A good approach to depth conversion, especially in a complex geological environment, is first to perform a depth migration with a velocity model optimized for structural imaging, second to render the resulting laterally positioned depth image to time using the provelocities, and finally to convert the depth migrated seismic data now in the. Dynamic depth conversion and map update dynamically build velocity models by tying your well and seismic data. Nov 20, 2018 how are seismic signals from a particular period of time transformed in depth. Work efficiently in time or depth with dynamic depth conversion. Peter wang, geophysical technical advisor gustavo morales, senior geophysicist, geophysical technical advisor.
Geophysics software seismic interpretation software. Sep 29, 2016 geovariances has already relevant experience in building time to depth conversion software, in particular with isatoil development, but this new potential tool will far exceed the former package. Comprehensive poststack velocity modeling for interpreters and depth conversion. Some methods can be done easily by the seismic interpreter, more complex. The process of transforming seismic data from a scale of time the domain in which they are acquired to a scale of depth to provide a picture of the structure of the subsurface independent of velocity. Box british gas houston in the oil and gas business, seismic time to depth conversion problems are best solved, in many cases, by looking for velocity versus depth relationships on a. How to get kingdom suite to convert your well depths to times by inputting a velocity equation scheiberenslin. Unlike the physicists definition of velocity as a vector, its usage in geophysics is as a property of a mediumdistance divided by traveltime. A small mean residual difference indicating an unbiased depth conversion and a low standard deviation meaning the method explains the depth quite well are indications of a. Introduction gocad offers conversion of horizons and seismic in the time domain to the depth domain and vice versa. Depth conversion concerns the seismic interpreter because seismic measurements are made in time, but the wells based on a seismic interpretation are drilled in depth. View the help topics for the software includes some faqs. He was the lead architect of tdq time depth conversion, mva migration velocity analysis, depth team express velocity model building and served as the chief architect of the decisionspace platform. Volume 83, issue 2 deciphering fractured rock properties from seismic wavefields.
How to convert depht in doubletime depthtwt, to depths. Geo expro a simple guide to seismic depth conversion i. Exploring the shallow subsurface, by burger, sheehan, and jones. Albeit rarely, a third option is to use normalincidence rays for depth conversion. Seismic velocities and depth conversion inhouse training by petroskills this course can be conducted on site at your location exclusively for your staff. Learn how to understand the methods for linking well and seismic information. The depth is then estimated from the simple geophysical relationship that depth velocity x time.
Time to depth conversion geological structures are picked from seismic profiles in the time domain. Each of these options requires converting the time migration velocity to a velocity model. Volume 83, issue 1 upcoming special section deadlines. Depth conversion domain conversion of seismic time interpretations and data is a basic skill set for interpreters. Get an optimal initial model for inversion and accurate uncertainty maps and volumes. Exploration and field development teams all over the world rely on it to make critical drilling decisions every. Depth conversion is an important step of the seismic reflection method, which converts the acoustic wave travel time to actual depth, based on the acoustic velocity of subsurface medium sediments, rocks, water.
Time to depth conversion simple and accurate timetodepth workflows with unique threecomponent horizons for time, velocity and depth data. Relationship between pointshaped scattering body and diffraction hyperbola, kirchhoff migration principle. As a simple rule of thumb, if you hit a rock with a geological hammer, fast rocks go. Through the integration of interpretation, velocity analysis, model building and updating, model validation, depth imaging, and timetodepth conversion, geodepth. Categorize the various time to depth conversion methodologies. Jones abstract many data processing and interpretation procedures are performed on time domain data. Domain conversion can be performed backward and forward between time and depth for any object, including surfaces, horizons, faults and multiz interpretations, points, well data logs and tops, 2d and 3d seismic data, and pillar and stairstepped 3d grids. The time to depth conversion strategy involves the following steps. Comprehensive horizon depth conversion options, each tailored to a different problem. Whether exploring complex structural areas or looking for subtle stratigraphic traps, todays geoscientist can use the many tools of gverse.
If such procedures are to be applied after a depth imaging project has been conducted, it is necessary to convert the data to the time domain from the depth domain. More recently, he served as the development manager of landmarks next generation cloud computing initiative. Velocity modeling estimages geostatistics for geophysics. Participants will gain an understanding of how to effectively design, guide, and quality control depth imaging projects in a variety of geologic settings and be able to.
The combination of the interval velocity maps from step c with the depth horizons from step d constitutes the initial model derived from time to depth conversion. The rate at which a wave travels through a medium a scalar or the rate at which a body is displaced in a given direction a vector, commonly symbolized by v. In fact, the new tool that will derive from the uncertz research will present several unheard features in any of the software packages currently. Course content depth conversion is approached as part of the geological geophysical interpretation process, starting during seismic time interpretation and ending with maps for stoiipgiip. Geo expro a simple guide to seismic depth conversion ii. The residuals are the difference between the depth predicted by the velocity model using the seismic time at the well marker and the actual depth observed in the well. Develop well tying techniques for maps derived from interpretation of depth domain seismic data based on good time domain depth conversion techniques. Additionally, cover the implementation of basic depth conversion using vertical functions and spatial corrections, as well as exploring depth. He is an acknowledged expert in interpretation, depth conversion, and depth imaging. Velocities for depth conversion and imaging geoenergy. Time horizons interpreted from the time migrated volume of data may first be forwardmodeled to derive 3d zerooffset traveltimes, which are then depth converted using normalincidence rays. Seismic velocities and depth conversion level skill 510 years experience instructor scott mackay mackay consulting corporation, inc. Optimize your time to depth conversion, at a prospect or a regional scale.
When the vo is measured from surface 0 meters you can calculate the depth using the following formula. Update home for field geophysical software suite that accompanies introduction to applied geophysics. Radexpro is a seismic processing software on windows. It is well suited for in depth hruhr marine seismic processing, real time marine 2d3d seismic qc, onboard fast track processing, land and marine offline seismic qc, complete processing of nearsurface seismic data reflection, refraction, tomography, masw and vsp processing.
Dug is an innovative company offering geophysics and a diverse range of geoscience, seismic, and cloud services for oil and gas. Downunder geosolutions offer an integrated approach to enable us to deliver results for our clients. Seismic velocity estimation and timetodepth conversion. Seismic interpretation software powerful, 2d and 3d seismic interpretation system for rapid prospect generation. Hence, we use the dix velocity instead of time migration velocity as a more convenient input.