A comparison of data acquired using two different land nodal recording systems as part of a 3D seismic survey

P054 An Integrated Project Design for a 3D seismic exploration survey in the Burgos basin Mexico Summary 1 MARCELO BENABENTOS * FRANCISCO ORTIGOSA* CHU-CHING-LI** TIM BROOKS ** The exploration and development plan for the Reynosa Monterrey block in the Burgos basin Mexico included the acquisition of new 3D seismic surveys and the reprocessing of the existent 3D seismic data. In January and February of 2004 Repsol-YPF and WesternGeco conducted an Integrated Project Design study with the following objective: to determine the optimum acquisition and processing parameters for two 3D seismic surveys. Based on this study in the summer and fall

The three-dimensional (3D) seismic survey is a relatively new technique used in the exploration and development of petroleum resources. It is well known that precise navigation (positioning) is required for the 3D seismic operation. However, it is not well understood why this high level of precision is required. In addition, few, if any, attempts have been made to discuss actual positioning achievements while performing a 3D seismic survey. This paper attempts to fill both these voids. In this paper, the 3D seismic survey is simply explained from basic principles and the position accuracy requirements are developed. State-of-the-art techniques and equipment are presented for positioning both the seismic vessel and the towed streamer containing an array of hydrophones. Results are presented for vessel positioning using the 450 MHz Syledis system in conjunction with a 2 MHz Argo system. A direct comparison of these two systems is given from data obtained during a 3D seismic survey. In addition, operational results are presented for the positioning of a towed hydrophone array. New techniques under development for positioning the seismic vessel and the towed hydrophone arrays are presented. The possible use of GPS technology for 3D seismic surveys is discussed and the system's impact for future work is evaluated. Conclusions are presented summarizing current 3D seismic accuracy requirements, the techniques and equipment required, results that can be expected, and what positioning technology can be expected in the future.

PEMEX has the distinction of reaching high quality levels in its exploration and production processes during recent years. Outstanding achievements have been obtained in both activities, getting a better understanding from our reservoirs and geological frameworks increasing, as a result, the hydrocarbon reserves in the country. One of the most important keys in getting these achievements has been the massive design and acquisition of both 3D seismic and High Resolution Geohazard surveys of excellent quality. These studies have provided a big amount of information to the multidisciplinary teams becoming a definitive support for making decisions regarding exploratory programs, the generation of localizations, the characterization of the oil fields and the exploitation outlines. This work shows some of the most important contributions of 3D seismic and High Resolution Geohazard surveys made to the multidisciplinary teams dedicated to the generation of localizations, navigation control during drilling of horizontal oil wells, as well as to the reduction of physical risk for the location of marine drilling rigs. We will also show an example of how the seismic bandwidth can be substantially increased through the use of top-technology 3D seismic surveys in the prolific Lankahuasa area. Finally, we will take a look on what is coming in terms of seismic design and acquisition in the PEP North Region for the near future.

Southern Ordos Basin contains plentiful oil and gas shale resources in the Mesozoic and Upper Paleozoic. It is known that the surface in this region is covered by thick loess layers with severe variations in tomography, thickness and velocity. The adverse surface conditions result in complex statics problems and heavy scattering noise and also cause serious absorption of high-frequency energy. Conventional seismic surveys obtain poor quality seismic data, which could hardly be used to obtain information about gas shale reservoirs. In order to study strong heterogeneous gas shale reservoirs and improve the success rate of horizontal wells, a new 3D seismic survey was acquired in the typical loess plateau area by using the WesternGeco UniQ integrated point-receiver land seismic system. The new survey is designed as full-azimuth, high-density, point-source/point-receiver in order to fully sample the seismic wavefield and avoid the irreversible signal damage caused by conventional field array techniques. By taking advantage of the benefits of UniQ seismic data, targeted data processing sequence is given to resolve the specific complicated statics and noise attenuation problems. Compared with the previously acquired 2D crooked line high-resolution seismic data in the gullies, the result of UniQ seismic data exhibits significant improvement both in the single-to-noise ratio (SNR) and the image quality of target layers. This indicates that the UniQ seismic data will be more feasible to facilitate gas shale characterization.

Japan CCS Co., Ltd. (hereinafter “JCCS”) has been conducting the investigation of potential CO2 storage sites in Japan undercontract to the Ministry of the Environment (hereinafter “MOE”) and Ministry of Economy, Trade and Industry (hereinafter“METI”) of Japan since 2014. We have been conducting a number of 2D/3D seismic surveys and geological interpretation at pre-selected areas in offshore Japan, in order to identify prospective sites from among these areas. Several candidate sites will be selected from these prospective sites, and exploratory wells will be drilled to confirm the presence of geological conditions necessary for storage. The drilling will be followed by the construction of a geological model and flow simulation. The final goal of the current scope of work is to recommend three potential sites for CO2 geological storage to MOE and METI by around 2021. The main selection criteria of a potential storage site are as follows: > The potential sites should be located in offshore areas > Capacity of each site is to store over 100 million tonnes of CO2 > There are no active faults close to the site > The existence of a CO2 emission source near the site is not taken into consideration > The method of CO2 transportation to the site is not taken into consideration > Producing oil and gas fields are excluded (site is not for EOR purpose) > There is no environmental protected area around the site In addition, a preferable condition is whether the site can be reached by directional drilling from onshore, as is the case for the Tomakomai CCS Demonstration Project. In this project, two directional CO2 injection wells were drilled with horizontal reach of over 3,000 meters, saving considerable construction cost as it was not necessary to bring in an offshore drilling rig, or to lay expensive subsea pipelines and related offshore facilities. The 2D/3D seismic survey conducted in the investigation of potential sites is the most effective method to delineate the geological features of the subsurface. 2D seismic surveys are conducted to grasp the regional geological features over a wide range such as 50 x 100 km, and if prospective structures for CO2 geological storage are identified, 3D seismic surveys over a smaller range (e.g., 10 x 10 km) will be executed to delineate the geological features more precisely. When necessary, we employ state-of-art seismic acquisition and processing technology utilized in the oil and gas industry to accomplish our objectives. In one of the 3D seismic surveys, we have conducted a seamless 3D seismic survey across the transition zone between shallow marine and onshore. As the possible presence of active faults was suspected in the transition zone, there was a need to collect data from the shallow marine continuously to the onshore area. Although the survey has taken time and effort, we were able to fill the gap in the existing seismic data between offshore and onshore with data of reasonable resolution utilizing an Ocean Bottom Cable (OBC). The geological interpretation found that the subsurface of the transition zone was a narrow synclinal valley along the current coastline with no active faults present, and therefore that it was possible to store CO2 in the offshore area as it was safely isolated from the populated onshore area. At another prospective site, we have conducted a 3D seismic survey utilizing broadband technology; the first application of this state-of-art technology in Japan. Because the target sandstone reservoirs in the survey area are composed of deep marine sediments such as turbidites and submarine fans, high-resolution 3D seismic data is required to differentiate the sandstone types. The high resolution data may be further utilized for special processing such as acoustic impedance (AI) inversion and amplitude versus offset (AVO) analysis which is help to evaluate rock properties in order to reduce geological risk. The high resolution near surface data acquired in broadband technology is also useful in identifying shallow gas hazards in the area. In BroadSeisTM(*), the broadband seismic technology we adopted, the slanted streamer cables are deployed deeper than conventional seismic surveys, mitigating the effects of sea surface swells and wave noises under rough sea conditions. As a result, we were able to reduce drastically the downtime due to rough weather during the survey period. (*: trademark of CGG) In summary, the application of state-of-art seismic acquisition technology in the investigation of potential CO2 storage sites is expected to reduce geological risk as well as contribute towards saving acquisition costs.

Three-dimensional (3-D) seismic surveys have become a major tool in the exploration and exploitation of hydrocarbons. The first few 3-D seismic surveys were acquired in the late 1970s, but it took until the early 1990s before they gained general acceptance throughout the industry. Until then, the subsurface was being mapped using two-dimensional (2-D) seismic surveys. Theories on the best way of sampling 2-D seismic lines were not published until the late 1980s, notably by Anstey, Ongkiehong and Askin, and Vermeer. These theories were all based on the insight that offset forms a third dimension, for which sampling rules must be given. The design of the first 3-D surveys was severely limited by what technology could offer. Gradually, the number of channels that could be used increased, leading to discussions on what constitutes a good 3-D acquisition geometry. The general philosophy was to expand lessons learned from 2-D acquisition to 3-D. This approach led to much emphasis on the properties of the CMP gather (or bin), because good sampling of offsets in a CMP gather was the main criterion in 2-D design. Three-D design programs were developed that concentrated mainly on analysis of bin attributes and, in particular, on offset sampling (regularity, effective fold, azimuth distribution, etc.). This conventional approach to 3-D survey design is limited by an incomplete understanding of the differing properties of the many geometries that can be used in 3-D seismic surveys. In particular, the sampling requirements for optimal prestack imaging were not properly taken into account. This book addresses these problems and provides a new methodology for the design of 3-D seismic surveys. The approach used in this book is the same as employed in my Seismic Wavefield Sampling, a book on 2-D seismic survey design published in 1990: Before the sampling problem can be addressed, it is essential to develop a good understanding of the continuous wavefield to be sampled. In 2-D acquisition, only a 3-D wavefield has to be studied, consisting of temporal coordinate t , and two spatial coordinates: shot coordinate x s , and receiver coordinate x r . In 3-D acquisition, the prestack wavefield is 5-D with two extra spatial coordinates, shot coordinate y s , and receiver coordinate y r . In practice, not all four spatial coordinates of the prestack wavefield can be properly sampled (proper sampling is defined as a sampling technique which allows the faithful reconstruction of the underlying continuous wavefield). Instead, it is possible to define three-dimensional subsets of the 5-D prestack wavefield which can be properly sampled. In fact, the 2-D seismic line is but one example of such 3-D subsets.

Relevance of the work. The paper considers challenging problems related with outlining of intervals with oil and gas presence in the mature Khylly field by use of latest 3D seismic survey techniques in order to gain larger crude resources base. The purpose of this research is to discover the most promising intervals of target horizons with relatively high reservoir properties outlined by 3D seismic data. The subjects of research are 3D seismic survey data, downhole seismic survey – Vertical Seismic Profiling (VSP) and well logging diagrams. The object of research is the Khylly deposit. The paper describes in brief geological and geophysical characteristics, stratigraphic and lithological features of rocks making the section. It is noted that despite repeated surveys by use of various geological and geophysical techniques, the field setting is not thoroughly studied and it has been covered by 3D seismic survey in 2012. Research results. 3D seismic survey applied across Khylly area is resulted in drawing of 4 structural maps for III and I horizons of Productive Series (PS), Akchagyl and Lower Absheron suites. Taking into account the relevance of structural planes of various stratigraphic levels and III horizon of PS being one of the major reference horizons the paper gives description of structural map drawn for this horizon. The detailed velocity model is designed based on VSP data with wide use of velocity analysis data. It has been made clear that Khylly area has block structure and each block has been described in detail. Based on acquired data it has been recommended to drill exploratory well R-1. Conclusion. Processing and interpretation of seismic data are aimed at solving some geological problems; the main task was to obtain results that ensure the study of the geological structure in the seismic survey area, including tracing of seismic horizons, faults and outlining the areas and section intervals which may be of interest due to possible oil and gas presence. VSP data acquired in well 2012 and velocity analysis made it possible to design velocity model of the section under the study, with the use of which the temporary 3D cube was transformed into a depth cube. The quality of seismic data is good and made it possible to solve the tasks set for this research.

PreviousNext No AccessSEG Technical Program Expanded Abstracts 2000Delineation of geological structures by 3D seismic surveys in Australian coal miningAuthors: Binzhong ZhouPeter HatherlyBinzhong ZhouCMTE/CSIRO Exploration and Mining, Australia and Peter HatherlyCMTE/CSIRO Exploration and Mining, Australiahttps://doi.org/10.1190/1.1815578 SectionsAboutPDF/ePub ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinked InRedditEmail Permalink: https://doi.org/10.1190/1.1815578FiguresReferencesRelatedDetailsCited byPrediction of coal seam details and mining safety using multicomponent seismic data: A case history from ChinaJun Lu, Xinghun Meng, Yun Wang, and Zhen Yang11 August 2016 | GEOPHYSICS, Vol. 81, No. 5Subsidence Assessment Using 3-D Seismic Data at Collingwood Park, BrisbaneBinzhong Zhou, Milovan Urosevic, and Baotang Shen26 August 2015 | Journal of Environmental and Engineering Geophysics, Vol. 20, No. 3 SEG Technical Program Expanded Abstracts 2000ISSN (print):1052-3812 ISSN (online):1949-4645Copyright: 2000 Pages: 2484 publication data© 2000 Copyright © 2000 Society of Exploration GeophysicistsPublisher:Society of Exploration Geophysicists HistoryPublished Online: 04 Jan 2005 CITATION INFORMATION Binzhong Zhou and Peter Hatherly, (2000), "Delineation of geological structures by 3D seismic surveys in Australian coal mining," SEG Technical Program Expanded Abstracts : 1101-1104. https://doi.org/10.1190/1.1815578 Plain-Language Summary PDF DownloadLoading ...

The Tengiz oil field in KAZAKHSTAN, located on the northern and eastern shores of the Caspian Sea, is a major oil field where Russia initiated production more than 25 years ago. In the past three years, Tengiz Chevron Oil (TCO) increased production significantly and was recently considering drilling new holes to boost output. To help to the selection of drilling locations, a 3D seismic survey using both vibrators and dynamite was conducted on the 400 km2 producing field. Because the location accuracy of the current buried pipe network is not sufficiently precise on available maps, a reconnaissance test took place at specific sites where old and recent pipes are known to exist. Most of these sites were also selected for their proximity to sensitive structures : plan facilities, manifold, dike edging the sea and office buildings where safety distances from seismic sources had to be determinated with a view to a forthcoming 3D seismic reflection survey.

In this paper, we present and demonstrate that the implementation of an efficient Project Management Strategy has effectively contributed in a safe and successful completion of a very complex 3D OBN Seismic Survey in congested Oil fields. Thus, delivering high quality data on schedule and within the predetermined budget at the full satisfaction of all involved parties and stakeholders. Strong commitment to HSSE Standards and working as an integrated One-Team with full collaboration and continuous communication between all the Team members are among the main Success Factors of the 3D seismic survey which was carried out during the critical period of COVID-19. Moreover, the deployment of experienced personnel, advanced and reliable Technologies with adequate equipment have also extended the efficiency of this OBN 3D seismic survey. Preliminary results of 3D seismic data processing, interpretation and reservoir characterization are also briefly presented and discussed as a clear enhancement of data quality was already observed compared to the legacy 3D OBC data set. A fast track small 3D cube was successfully processed as an utmost and urgent priority for appraisal well selection, design and drilling.

This paper aims to improve reservoir characterization of sandstone reservoirs in the Khafji oil field, Arabian Gulf, by integration of well test analysis and fault location information from three-dimensional (3D) seismic survey. There are several hundreds of normal faults in the Khafji field which were recently recognized by 3D seismic survey. Although the reservoir has strong edge water drive, water production is observed in some central upstructure area earlier than in peripheral area nearby. Existence of conductive faults, which causes fluid communication between the upper and lower reservoirs, was suspected from engineering analyses conducted. Conductive faults have great impact on reservoir water production and pressure behavior. The main issues of this paper are: Well test analysis for wells near 3D seismic interpreted faults.Design of interference test to investigate vertical fluid communication through conductive faults between two reservoirs. Well test data for 5 selected wells located near faults were analyzed and boundary effects such as sealing fault or constant pressure were interpreted. Faults located within 1000 feet distance from wells were characterized by integration of well test and 3D seismic results. Field test was designed in an area where interference between the Upper Sand and the Lower Sand was suspected. 1 active well and 4 passive wells were designed and pressure behavior of each well was predicted. A fault was defined in the model by placing two adjacent rows of cells with 30 feet difference in depth. Fault conductivity was changed as a parameter in simulation. Two kind of tests were discussed: (1) Short term interference test with 3 pulses of 12 hours each (2) Long term interference test with 3 pulses of 1 week each. Long term interference test was recommended from the simulation results because pressure drop was detectable even when fault conductivity was small.

The success of an exploration or development project hinges on a knowledge of the subsurface. This is true whether we are locating an exploration well, or planning the development of a discovered field. Three-dimcnsional (3D) seismic surveys have proved to be powerful tools for imaging the subsurface. Since their introduetion in the mid- 1970s, 3D seismic surveys have provided data that have been shown to be significantly superior to 20 seismic data, both for structural imaging and for detailed characterization of reservoir-rock properties and porefluid content.

Indonesia is resolutely addressing climate change with a commitment to reduce carbon emissions by 29% in 2030, and we are on track to achieve net-zero emissions in 2050. This country acknowledges the important role of Carbon Capture, Utilization, and Storage (CCUS) in mitigating carbon emissions, especially from the energy sector, and at the same time increasing oil and gas production. This kind of approach is also well known as CO2-EOR (Enhanced Oil Recovery) and CO2-EGR (Enhanced Gas Recovery). Sukowati field is situated in the East Java Province and will serve as a pioneering CO2 Enhanced Oil Recovery (EOR) project aimed at revitalizing the field. This initiative focuses on increasing oil production while capturing and storing carbon dioxide (CO2), contributing to environmental sustainability. To ensure its success, a robust monitoring system must be implemented for real-time data collection and analysis, optimizing recovery processes and minimizing environmental impact. Monitoring activities deliver information regarding the CO2 injected into the reservoir and the risk of leakage into the surrounding injection region. Several methods are discussed for monitoring CO2 plumes, but in the subsurface, seismic methods stand out as the most promising option. However, despite their effectiveness, seismic methods are also among the most expensive to execute, necessitating significant investment in technology and expertise to ensure accurate and reliable data. 4D seismic, also known as time-lapse seismic, entails performing repeated seismic surveys over a designated area to monitor changes in the subsurface effectively. This imaging technique enables us to visualize the movement of CO2 plumes within the target formation and can identify alterations in the reservoir that may suggest a potential CO2 leak. A seismic survey before the injection is needed to create a baseline image of the subsurface target reservoir. Changes in velocity and amplitude are identified when the seismic waves encounter the CO2 plumes injected into the reservoir target. The challenges of performing a 4D seismic imaging survey in a densely populated area are social impact, the possibility of damaging infrastructure, high noise levels, and high operating costs, particularly if it uses a subterranean explosive (dynamite) as a source of seismic signals. To address these challenges, the study introduces a novel approach to designing irregular 4D seismic surveys. This method features a flexible acquisition layout that departs from traditional geometric symmetry. The survey utilizes a non-impulsive (vibrator) of semi-permanent seismic source and a highly sensitive, wireless seismic recording system. The irregular design is adaptively tailored based on the field's spatial characteristics, potential surface disruptions, and cost considerations. Despite not adhering to a conventional grid or orthogonal configuration, this approach ensures adequate offset and azimuth coverage necessary for detecting subsurface changes.

"4D seismic reservoir monitoring" is the process of repeating 3D seismic surveys over a producing reservoir in time-lapse mode. It has a potentially huge impact in reservoir management because it is the first technique that may allow us to directly image dynamic reservoir processes such as fluid movement, pressure build-up, and heat flow in a reservoir in a true volumetric sense. However, its simple underlying concept is complicated by practical operational issues. These include having the right mix of business to justify a 4D seismic project, a favorable technical risk assessment and feasibility study, highly repeatable seismic acquisition survey design, careful high-resolution seismic data processing, and an ultimate reconciliation of 4D seismic images with independent reservoir borehole data and history-matched flow simulations. The practical difficulties associated with 4D seismic suggest that this new technology is not a panacea, but rather that it is an exciting emerging technology that requires very careful analysis to be useful. Introduction "4D seismic reservoir monitoring" is the process of repeating 3D seismic surveys over a reservoir in time-lapse mode to look for differences caused by production. The potential exists for dramatic benefits to reservoir management because it is the first technique that may allow us to directly image dynamic reservoir processes such as fluid movement, pressure build-up, and heat flow in a reservoir in a true volumetric sense. To understand this, let us review the seismic method, and then consider what advantages the time-lapse aspect of 4D seismic brings. In a single 3D seismic survey, seismic waves are generated by sources (dynamite, airguns, etc.) at or near the earth's surface. These source waves reflect off of subsurface seismic impedance contrasts, which are a function of rock and fluid compressibility, shear modulus and bulk density, and are recorded as they arrive back at the earth's surface. The recorded waves form the classic wiggle traces where high positive amplitude portions are often filled in on a black and white image to enhance visual contrast and show lateral continuity. A wave-equation imaging algorithm is applied to the recorded reflection data to create 3D seismic images of the reservoir rock and fluid property (seismic impedance) contrasts. 4D seismic analysis simply involves repeating the 3D seismic surveys and analyzing images in time-lapse mode, to monitor time-varying fluid-flow processes during reservoir production. 4D seismic has all the traditional benefits of 3D seismic, plus a major additional potential benefit that fluid-flow processes can be directly imaged. To first order, seismic images are sensitive to spatial contrasts in two distinct types of reservoir properties:non-time-varying static geology properties such as lithology, porosity, shale content; andtime-varying dynamic fluid-flow properties such as fluid saturation, pore pressure and temperature. Given a single 3D seismic survey, representing a single snapshot in time of the reservoir, the static geology and dynamic fluid-flow contributions to the seismic image are non-uniquely coupled and therefore difficult to separate unambiguously. For example, it may be impossible to distinguish an oil-water contact from a horizontal depositional boundary in a single seismic image. However, with 4D seismic surveys, examining the difference between time-lapse 3D seismic images allows the non-time-varying geologic contributions to cancel, resulting in a direct image of the time-varying changes caused by reservoir fluid flow. For example, an oil-water contact may move with time in a series of time-lapse seismic images, whereas a depositional boundary should not. In this way, the 4D seismic technique has the potential to image, in a large volume encompassing many wellbores, changes in fluid saturation, pore pressure and temperature during production. 4D seismic reservoir monitoring promises to add significant improvements in our ability to estimate saturation and pressure distributions from sparse well control and flow simulations. P. 449^

In support of the South Florida Water Management District (SFWMD) Floridan Aquifer System (FAS) and Aquifer Storage & Recovery (ASR) groundwater development & management programs, high resolution broadband seismic test data was acquired and processed in the Lake Okeechobee area. As part of the FAS and ASR development plans SFWMD identified the need for improved delineation and characterization of the FAS in terms of stratigraphic and hydro-geologic structure. High resolution 2D and 3D seismic acquisition, data processing & modeling, and integrated well log analysis, originally developed for deep oil and gas exploration, have been successfully adapted for high-definition geomorphologic and intra-stratigraphic characterization of the Floridan Aquifer System to depths in excess of 3,000 feet (bgs). In addition, the seismic survey programs were designed to evaluate the potential for identifying zones of deep karst structures that can provide hydro-geologic information concerning vertical and lateral flow of groundwater between major permeable zones within the Floridan aquifers. Based on results from the 2D and 3D seismic test surveys it is shown that the required seismic bandwidth of processed seismic data to identify complex FAS faults and fracture systems is approximately 10 Hz to 120 Hz. The required broadband seismic data is also essential for additional attributes processing to identify zones of intra-stratigraphic karst structures that can affect the long term migration and/or containment of groundwater within FAS confined aquifers. Location and seismic attributes knowledge of faults and fractures systems, augmented with detailed borehole and well log information, is critical to the future placement and installation of deep injection and groundwater production wells. In this presentation, we identify the areas of investigation and local FAS geology, summarize aspects of the seismic surveys, and present modeling and interpretation examples from the 2D and 3D data. From the SFWMD Lake Okeechobee seismic test program we present a summary review of other seismic methods and applications for future development and adaptation to similar groundwater exploration and aquifer investigation projects.