Seismic attributes which are calculated using more than one seismic trace as input. Wide azimuth seismic processing for uae carbonate reservoir. The company recently reported that it has started acquisition of the latest phase of the cygnus regional multiclient 3d survey in the vulcan sub. Please note that we are still in the process of updating our entire database.
Amplitude variation with azimuth at different offset of reflected seismic wave from the interface or the top of the hti layer in the model figure 2. It provides information on computer systems, data processing, time series analysis, seismic data processing, migration and inversion theory and practice. Acquiring more azimuths for improved offshore seismic. Read more about this novel configuration and the superior imaging. Redefining multiazimuth seismic acquisition hart energy. Later work was on inversion of multicomponent reflection data and multiazimuth walkaway vsp surveys. Intuitively, a wideazimuth survey that collects long offset data from all directions might seem to be better but this is not always the case. An innovative method improves spatial sampling and adds complementary azimuths from new multisensor broadband acquisition to enrich. A progression in survey effort from one vessel towing sources and streamers sailing a survey area in two or more directions to several vessels sailing a survey area in two or more directions, some of them possibly only towing sources, represents the operational contrasts between multi azimuth maz, wide azimuth waz, and full azimuth faz 3d seismic. Offshore, obc are commonly used to acquire wideazimuth data.
Porosity characterization in a silurian reef, northern. Multicomponent, multiazimuth prestack seismic waveform. Obstacles in the analysis of azimuth information from prestack seismic data. Acquisition and processing of marine seismic data sciencedirect. Multiazimuth streamer seismic in the nile delta part 1. Multiazimuth vsp surveys are used to tie the interpretations of azimuthal anisotropy, carried out at the seismic scale, to the anisotropy and fracture measurements, which have been carried out. The azimuth is usually specified in degrees with respect to the geographic or magnetic north pole. Use of dip and azimuth horizon attributes in 3d seismic.
These include operational noise, air gun bubble, multiple reflections, swell noise. The companys seismic processing technology extracts shearwave seismic information from any vertical force source for both vsp and surface seismic studies, enabling geophysicists to improve drilling and production decisions and also reduce cost and time barriers associated with multi. Wide azimuth surveying is appropriate for any area of complex structural geology or where velocity contrasts are significant and salt causes imaging problems, the area that has seen the greatest application of wide azimuth acquisition is in the gulf of mexico and since 2008 wide azimuth surveys have been recorded in other areas. An ultra high density, full wide azimuth seismic survey for the future jeanjacques postel cggveritas 2nd finding petroleum event on onshore seismic. The method requires a controlled seismic source of energy, such as dynamite or tovex blast, a specialized air gun or a seismic vibrator, commonly known by the trademark. This book emphasizes the practical application of seismic data processing methods. Velocity model with azimuthal anisotropy was used for the final maz psdm. Acquisition and processing of azimuthal vertical seismic profiles at multiwell experiment site, garfield county, colorado. Seismic data offers an indirect measure of the effects of fracturing either through measuring shearwave splitting multicomponent acquisition and processing, azimuthal variations in pwave velocity, azimuthal avo or poststack techniques like curvature analysis, coherence or inversion. The use of multicomponent data pp and ps collected over anisotropic sedimentaryrocks for reservoir characterization and exploration. Nevertheless, to realize the added value of multiazimuth data, the data need to be. In fact, most early 3d seismic surveys were narrow azimuth, although it was probably a matter of necessity as much as intentional design. Further qc of the field geometry was with increasing azimuth sort within 200m offset bins. Azimuth is the angle at the source location between the sail line and the direction to a given receiver.
Heloise lynn specializes in the expression and use of anisotropy in multidimensional datasets multiazimuth, multicomponent, and time lapse, 3d azimuthal seismic acquisition design, azimuthal seismic processing, and azimuthal seismic interpretation. Wide and fullazimuth surveys including stagseis fullazimuth. In basins with moderatetodeep objectives, the number of channels in the recording system restricted the contractors ability economically to acquire wide azimuth seismic data. All legacy files are available on the old earthdoc website, which you can access via the button below. A narrated presentation that provides an overview of wide azimuth data processing. In 20092010, shells use of wideazimuth seismic surveys led to. Multicomponent seismic and anisotropy for oil and gas. Walt is a pastpresident 200102 and an honorary member of the society of exploration geophysicists and an honorary member of geophysical society of houston. Multiazimuth versus wideazimuth acquisition designs for sub. The models can be used to subtract noise patterns or enhance seismic events and improve the signaltonoise ratio in poor quality datasets. The current volume, multicomponent seismic technology seg geophysical references series no. Acquisition and processing of azimuthal vertical seismic.
A case study dealing with azimuthal velocity anisotropy. Using real multiazimuth maz seismic data from northwest australian shelf the paper shows how this problem can be solved by depthvelocity modeling with maz tomography that takes into account both real and apparent anisotropy. Supervise seismic data processing activities to preserve azimuthally dependent parameters such as travel times, frequency, phase, and avo. Catalog numbers for ebooks typically are the print cat.
Restructured seismic industry cautiously optimistic offshore. We have the most advanced and recent seismic data library in the worlds most prospective. Seismic azimuthal anisotropy and fracture analysis from pp. Multiattributes display and rose diagrams for interpretation. Seismic data processing methods must address the interference introduced by simultaneous overlapping sources. Wide azimuth while multiazimuth seismic has proved successful in the nile delta, it is not necessarily the key to subsalt imaging in the gulf of mexico. Acquisition and processing of azimuthal vertical seismic profiles at multiwell experiment site, garfield county. Society of exploration geophysicists much has changed since seg published a comprehensive book on multicomponent seismic technology in 1991. Multicomponent, multi azimuth prestack seismic waveform inversion for azimuthally anisotropic media using a parallel and computationally efficient nondominated sorting genetic algorithm tao li department of geology and geophysics and the school of energy resources, university of wyoming, laramie, wy 82071, usa. Meeting of the consortium project on seismic inverse methods for complex structures, may 1215, 2014. The azimuth information derived from prestack seismic data at target layers is very sensitive to many aspects of the analysis process, making reliability a serious issue. The dip and azimuth models are seismic attributes used to help with structural interpretation. Pgs is redefining marine towedstreamer acquisition oil and gas. Multi azimuth maz, wide azimuth waz or full azimuth faz seismic acquisition overcomes the limitations of the conventional acquisition in better illuminating the subsurface, suppressing the multiple and enhancing signal to noise sn ratio.
Relevant computer hardware and procedures in a seismic data processing laboratory are discussed. Heloise lynn specializes in the expression and use of anisotropy in multi dimensional datasets multi azimuth, multi component, and time lapse, 3d azimuthal seismic acquisition design, azimuthal seismic processing, and azimuthal seismic interpretation. Walt specializes in multiazimuth, multicomponent 3d seismic acquisition, processing and interpretation and an adjunct associate professor at the colorado school of mines. Use of dip and azimuth horizon attributes in 3d seismic interpretation authors jaap c. The target essentially is illuminated from one direction in naz surveys. Here the challenges are different, as the mobile salt horizon results in variations in wavelength and thicker bodi. Us7391673b2 method of wide azimuth seismic acquisition.
Reflection and refraction seismic methods springerlink. Multicomponent data acquisition and the various ways of multicomponent data processing will be treated and a full understanding of anisotropy will be provided. Multiattributes display and rose diagrams for interpretation of seismic fracture lineaments, example from cuu long basin, vietnam ha t. Africa cenozoic data processing egypt geophysical methods upper miocene neogene messinian miocene nile delta north africa tertiary. Quantifying and increasing the value of multi azimuth seismic the leading edge tectonic evolution of the eastern mediterranean basin and its significance for hydrocarbon prospectivity in the ultradeepwater of the nile delta.
A first challenge was to reprocess these data ensuring that the azimuthal information is properly preserved all along the sequence. The overall objective of this course is to introduce entry level andor junior geophysicists and geoscientists to the essential acquisition and technical processing concepts and principles that form the basis for value added seismic applications in exploration, field appraisal, and reservoir. Acquiring more azimuths for improved offshore seismic resolution. Recent advances in marine seismic acquisition and processing. Shell addresses these challenges by combining novel acquisition technologies with a. In the multiazimuth case, the survey is acquired a number of times in different. In a multi azimuth maz survey the seismic vessel acquires 3d seismic data over the survey area in multiple directions, up to six. Apr 05, 2020 multiazimuth maz and fullazimuth faz marine seismic coil shooting long offsets. Target interval azimuth 0 azimuth 45 azimuth 90 azimuth 5 mean 1sd q. Assess the relevance of various seismic attributes from azimuth sectored prestack time migrated 3d data. Coca 9x9 cmp supergather same cmpsolution was generated. Wideazimuth processing for reservoir characterization.
We are used to the convenience of acquiring overlapping shot gathers in straight lines, as we can sort the data into common. This operation, in effect, extracts an individual 2d seismic line from within the 3d data volume. The latest pgs multiazimuth seismic concept, called geostreamer x. Multiazimuth maz and wideazimuth waz acquisition 3 conclusions multiazimuth and wideazimuth marine acquisition geometries aim to provide a diversity of sourcereceiver azimuths in the recorded data. The number of vessel owners continues to shrink, this reshaping of the seismic industry should give polarcus an expanded client base of more multiclient companies that do not own vessels. A case study with acquisition and processing of a real 3d ninecomponent seismic survey combines all aspects of multicomponent seismic and anisotropy and concludes this course.
In addition, andrey created a tool to predict 4d timelapse seismic response of a reservoir using realistic fluidflow models and seismic transformations. This situation is taken care of in processing, by azimuth sectoring the ps data prior to imaging, since very few processing contractors have explicit code for azimuthal anisotropy embedded within ps 3d wideazimuth data. The companys seismic processing technology extracts shearwave seismic information from any vertical force source for both vsp and surface seismic studies, enabling geophysicists to improve drilling and production decisions and also reduce cost and time. Seismic reflection and refraction methods are routinely used to illuminate subseafloor geological relationships. Following the acquisition of the baseline survey, a standard seismic processing sequence was performed on the data set. Learn from anywhere using virtual courses with realtime interaction, elearning courses tailored to your pace of learning, and a full media library of course recordings and media from the brightest minds in geophysics all convenient, easytouse, and affordable.
Dip azimuth semblance and enhancement crestone seismic. In a multiazimuth maz survey the seismic vessel acquires 3d seismic data over the survey area in multiple directions, up to six. Mar 12, 20 acquisition and processing of azimuthal vertical seismic profiles at multiwell experiment site, garfield county, colorado. Seismic processing programs 140 might be conveyed into the computer that is to execute them by means of.
In addition to providing excellent structural images, the dense sampling of a 3d survey can sometimes make it possible to map reservoir quality and the distribution of oil and gas. Nevertheless, to realize the added value of multi azimuth data, the data need to be. Multiazimuth maz, wideazimuth waz or fullazimuth faz seismic acquisition overcomes the limitations of the conventional acquisition in better illuminating the subsurface, suppressing the multiple and enhancing signal to noise sn ratio. Numerical estimation of the instantaneous dip and azimuth of reflectors within a seismic volume see marfurt et al. It is assumed multiazimuth streamer acquisition for attenuation of diffracted that naz acquisition and processing is unable to meet the multiples, 72nd annual international meeting, seg, expanded data quality objectives in areas affected by geological barri abstracts, 8992.
Reflection seismology or seismic reflection is a method of exploration geophysics that uses the principles of seismology to estimate the properties of the earths subsurface from reflected seismic waves. The models can be used to create additional seismic attributes like 3d volumetric curvature. Multicomponent, multiazimuth prestack seismic waveform inversion for azimuthally anisotropic media using a parallel and computationally efficient nondominated sorting genetic algorithm tao li department of geology and geophysics and the school of energy resources, university of wyoming, laramie, wy 82071, usa. The dipazimuth combination which has the highest coherence is assigned to be the instantaneous dipazimuth for the point at. Multi azimuth vsp surveys are used to tie the interpretations of azimuthal anisotropy, carried out at the seismic scale, to the anisotropy and fracture measurements, which have been carried out. Obstacles in the analysis of azimuth information from. Later work was on inversion of multicomponent reflection data and multi azimuth walkaway vsp surveys. Experience shows that maz acquisition and processing is unable to resolve the challenging noise problems in salt. Additionally, specialized processing was performed on this baseline 3d survey in order to develop multiazimuthal 3d volumes, which are discussed in the next section. Similarly, a vertical plane of seismic data may be taken at an arbitrary azimuth through the volume by collecting and displaying the seismic traces that lie along a particular line. Optimal stacking for multiazimuth prestack seismic data.
Wide azimuth while multi azimuth seismic has proved successful in the nile delta, it is not necessarily the key to subsalt imaging in the gulf of mexico. Multi azimuth and wide azimuth clearly will thus have prominence. Sep 19, 2017 a progression in survey effort from one vessel towing sources and streamers sailing a survey area in two or more directions to several vessels sailing a survey area in two or more directions, some of them possibly only towing sources, represents the operational contrasts between multi azimuth maz, wide azimuth waz, and full azimuth faz 3d seismic. Please bear with us as we complete this move to a more robust system. In order to achieve these benefits, seismic processing and imaging need to address some. Here the energy ratio of the transverse to radial component as a function of azimuth indicates the symmetry directions since in the symmetry planes only the. Birdus cggveritas abstact multi and wideazimuth seismic data acquisition and processing can deliver dramatic improvements in the subsurface illumination, imaging and studies of rock properties. Developer of a seismic processing technology designed to offer multi component seismic analysis. Reflection seismology, more commonly referred to as seismic reflection or abbreviated to seismic within the hydrocarbon industry, is used by petroleum geologists and geophysicists to map and interpret potential petroleum reservoirs. We use the term multiazimuth seismic maz to refer to the combination of. My recent work documents how touse the anisotropy recorded in wideazimuth 3d.
We present in this work an exhaustive seismic study which was performed on a subset of a wide azimuth ocean bottom cable seismic acquisition shot over a carbonate field from the u. Pdf multiazimuth towed streamer 3d seismic in the nile delta. Time imaging by walter rietveld bp has been acquiring multi azimuth maz streamer seismic in the nile delta since 2003. If only pwave sources are used, multiazimuth vsp or surface seismic data provide the means to analyse converted wave splitting for fracture detection e. Wide azimuth or waz is a term describing a seismic data acquisition technique where separate source vessels are used to record seismic reflections from areas out to the side of the recording spread. Construct workflows using multi attribute seismic data to characterize unconventional reservoirs. The compass direction of a directional survey or of the wellbore as planned or measured by a directional survey. Seismic amplitude is an invaluable daytoday tool for graduate students and industry professionals in geology, geophysics, petrophysics, reservoir engineering, and all subsurface disciplines making regular use of seismic data.
Heloise bloxsom lynn geophysicistlynn incorporated, 14534 westway lane, houston, tx 77077phone. May 23, 2010 it is assumed multiazimuth streamer acquisition for attenuation of diffracted that naz acquisition and processing is unable to meet the multiples, 72nd annual international meeting, seg, expanded data quality objectives in areas affected by geological barri abstracts, 8992. Construct workflows using multiattribute seismic data to characterize unconventional reservoirs. The size and scale of seismic surveys has increased alongside the significant concurrent increases in. Developer of a seismic processing technology designed to offer multicomponent seismic analysis.
A schematic 2d representation of the dip azimuth calculation. Jul 27, 2011 a narrated presentation that provides an overview of wide azimuth data processing. Walt specializes in multi azimuth, multi component 3d seismic acquisition, processing and interpretation and an adjunct associate professor at the colorado school of mines. This chapter represents a brief introduction to seismic data processing and provides. If only pwave sources are used, multi azimuth vsp or surface seismic data provide the means to analyse converted wave splitting for fracture detection e.
Wide azimuth processing for reservoir characterization. Quantifying and increasing the value of multiazimuth seismic the leading edge. During the last ten years, i have personally worked 18 eighteen 3d pp wideazimuth fielddata surveys andor 3d. Acquisition and processing of multisource broadband marine seismic data us10120087b2 en.
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