Efficient acquisition of large-scale, azimuth-rich ocean bottom node (OBN) data, with long offsets and high fold is now a reality. Such data provide an.
The Faroe Shetland Basin area located to the West of the Shetland Islands is typified by complex structural features with highly variable velocities,.
Ocean Bottom Node (OBN) data can be acquired using blended acquisition or simultaneous shooting that allows temporal overlap among different sources. A.
In ocean bottom seismic data, vertical components are frequently contaminated by converted shear waves due to the scattering in the shallow seabed. Proper.
Ocean Bottom Node (OBN) acquisition provides ultralong offset and full-azimuth (FAZ) illumination for better model building and imaging. A blended-source,.
Iterative data-domain least-squares migration can overcome acquisition limitations and recover the reflectivity for desired amplitudes and resolutions..
Least-squares imaging of primary reflection can overcome acquisition limitations and recover the reflectivity for desired amplitudes and resolutions (Wang.
One of the advantages of ocean bottom seismic data is combining hydrophone and vertical geophone data for ghost reflection attenuation. However, when the.
Due to inherent benefits such as ultra-long offset, full azimuth (FAZ) illumination and low-frequency availability, a large multi-client sparse-node.
We propose a multi-channel dynamic matching full-waveform inversion (DMFWI) for a high-resolution velocity-model update, which focuses on solving.
Imaging artifacts caused by strong internal multiples can interfere with primary images, affecting structural interpretation and amplitude analysis. In.
When a seismic wave propagates in the subsurface of the earth, its energy can be attenuated. This has a negative influence on both the amplitude and the.
The massively parallel nature of Graphics Processing Units has made them an attractive platform for some computationally intensive algorithms. This.
The Lower Zubair sand reservoirs have produced or shown oil in several but not all of the wells drilled in western and southeastern Kuwait. Evidence from.
Conventional marine seismic data is affected by the interference from ghosts on both the source and receiver sides. The natural diversity provided by.
The Angola basin is characterized by steeply dipping sediments with rapid changes in dip direction particularly in mini-basins between salt bodies. This.
We develop an efficient scheme of illumination analysis along a target horizon. With this scheme, we can calculate the Directional Illumination (DI) from.
We present a case study of the salt model building for a Gulf of Mexico area with a full azimuth (FAZ) dataset that was created by merging two orthogonal.
We have developed an enhanced methodology for creating a 3D seismic migration volume from a set of 2D seismic lines. The key challenge is to interpolate.
In land multi-component (MC) data processing, the orientation of each receiver's horizontal components in the field (H1 and H2) is seldom known.
As shale gas resources have emerged as a viable energy source, their characterization has gained significance. The organic content in these shales which.
In a marine environment, topographic features on the sea floor will usually be covered by a thick layer of shale with the rise of sea level, resulting in.
In RTM imaging, double top salt (DTS) is frequently seen but difficult to remove by conventional post-RTM processing. This paper analyzes the DTS.
A frequency domain tomographic inversion was developed to estimate frequency dependent energy attenuation by using prestack depth migration common image.
Two methods have recently been published for carrying out nonstationary spectral broadening (and narrowing) of PS data after it has been mapped into the.
Broadband seismic aims to provide a greater richness of both (a), robust low frequencies – ideal for deep structure imaging, and (b), high frequencies –.
Lifetime stability and reliability of fibre-optic seismic sensors for permanent reservoir monitoring
Permanent reservoir monitoring (PRM) using seabed arrays of seismic sensors is becoming a well recognised tool for optimizing production and increasing.
A 3D inversion based Least-Squares Reverse Time Migration (LSRTM) technique was developed. The algorithm uses the RTM as the forward modeling and.
The technology of using Tilted Transverse Isotropic Reverse Time Migration (TTI RTM) for subsalt velocity model building has been playing an important.
Seismic curvature attribute analysis forms an integral part of most interpretation projects as they yield useful information that adds value for the.
In this abstract, we describe how to improve time domain full waveform inversion using source wavelet convolution, windowed back propagation and source.
We present an imaging methodology that resulted in significant enhancements in defining the subsurface geology in a survey in the Appalachian Foothills..
The data driven 3D true azimuth Common Focusing Point (CFP) data regularization technique is a multi-dimensional data regularization tool. It can be used.
We propose a time-domain approach to transform a gather of pre-stack seismic data into an ensemble of highlyresolved traces in the transformed domain..
Extensive sequences of flood basalts dominate the northwest European Atlantic margin. The basalt flows absorb and scatter the higher frequencies present.
Shot based pre-stack depth migrations such as RTM are used to generate a partial image volume for each input shot gather. The conventional migrated image.
Anelastic properties of the earth cause frequency dependent energy attenuation and phase distortion in seismic wave propagation. It is preferred that.
Increased industry exploration interest in the Tarakan Basin, offshore East Kalimantan, Indonesia, has stimulated a need for 3D seismic data that.
5D interpolation methods have proven to be capable of overcoming the constraints of actual data acquisition in a wide range of situations. However, in.
The discrimination of fluid content and lithology in a reservoir is an important characterization that has a bearing on reservoir development and its.
We present results from a case study being performed in the Gulf of Mexico (GoM) that utilizes two orthogonal Wide Azimuth (WAZ) surveys to create an.
The implementation and production application of fast Reverse Time Migration (RTM) algorithms, especially for Tilted Transverse Isotropic (TTI) medium, is.
Tilted Transverse Isotropic (TTI) Reverse Time Migration (RTM) is routinely used for depth velocity model building. To improve the efficiency of RTM we.
We present an advanced velocity model building and imaging methodology that resulted in significant enhancements in defining the salt flanks with.
The Hoop Fault complex in the Southwestern Barents Sea presents an imaging challenge to accurately model the sharp velocity contrast across a major fault.
Three expanding domain methods are studied which include: (1) constant velocity layer, (2) eikonal equation solver and (3) amplitude comparison. The layer.
A velocity anomaly zone with high contrasts and small wavelength variations is often a challenge for conventional depth imaging. It requires model details.
Delayed Imaging Time (DIT) scans based on Reverse Time Migration (RTM) are often used in production to update velocity models, particularly in subsalt or.
We have applied layer-stripping Reverse Time Migration (RTM) to several Gulf of Mexico (GOM) depth imaging projects. The key element of layer-stripping.
We present a redatuming data regularization technique based on a 3D true azimuth Common Focusing Point (CFP) technique. It can effectively merge different.
Here we present a case study of improved subsalt imaging for a wide azimuth (WAZ) survey in the Mississippi Canyon/Atwater Valley area in the Gulf of.
A simultaneous anisotropic tomographic inversion algorithm is developed. Check shot constraints and appropriate algorithm preconditioning play an.
Creating an angle gather is a conceptually simple process of plotting reflection amplitudes along the angle. Reflection or opening angle can be directly.
A novel, de-aliased method called Stepwise Multiple Elimination using Linear Transforms (SMELT) is introduced as an alternative to 2-D Surface Related.
In the implementation of TTI RTM, we meet stability problems and demands for speedup. Staggered Fourier first derivative and linear interpolation improves.
A joint contractor-company project was undertaken to evaluate the practicality and utility of shallow high resolution reprocessing of large deepwater.
In efforts to further improve final migrated images we have developed a new methodology for post-migration multiple removal in the migration depth domain..
We present a case study of enhanced imaging of wideazimuth data from the Gulf of Mexico utilizing recent technologies; and we discuss the resulting.
A data driven 3D true azimuth surface related multiple elimination (SRME) technique can be quite effective in removing surface related multiples for both.
The long history of imaging in this area will be reviewed. Incremental improvements in data quality and interpretability will be shown. Processing efforts.
A new salt velocity model building methodology is proposed which allows effective testing of different salt interpretation scenarios. In this methodology,.
There has been a continually expanding interest in wide azimuth (WAZ) data in all its variations. We are now challenged to take full advantage of the.
To identify and define a complex salt body with rugose top and base is essential in building an accurate velocity model for premium quality depth imaging..
We have developed a new methodology for predicting and removing multiples in the migration depth domain based on wavefield extrapolation and attribute.
To attain the benefits of simultaneous shooting in marine data acquisition, either the simultaneous sources have to be placed far apart to minimize the.
A constrained propeller ship noise removal technique for OBC data has been developed. The constraints include the ship lane information, global linear.
The conventional zero-lag crosscorrealtion imaging condition of reverse-time migration is subject to strong migration artifacts. This paper studies.
Better de-multiple results are achieved by combining the strengths of SRME and wave field extrapolation techniques. In this paper, we illustrated three.
Wide-azimuth (WAZ) data is the most significant advance to have occurred in seismic acquisition and processing since the introduction of 3D seismic in the.
We present a case study of an anisotropic prestack depth migration (APSDM) project which used high-resolution, shallow tomography and anisotropic model.
The workflow for the practical application of the automated focusing analysis in time domain is demonstrated by deriving the TTI anisotropy parameters,.
Time domain and depth domain focusing operators are introduced to estimate anisotropic parameters. The fully automated time domain focusing operator to.
Accurate salt interpretation involves an integration of geology and geophysics. In the practice of salt interpretation and model building in depth.
It is well understood that accurate salt interpretation is critical to subsalt imaging. When reflections from the saltsediment boundaries are not.
Immediately offshore of the Mississippi Delta the geological setting conspires with numerous production installations to produce a unique set of problems.
Seismic anisotropy refers to seismic waves traveling with different velocity at different propagation angle, usually in consolidated, shale-prone areas.
Despite the development of excellent techniques for predicting multiples such as convolution based or wavefield extrapolation based approaches,.
Salt model building is a key process for successful subsalt imaging. In complex areas, Reverse Time Migration (RTM) provides better images than One-way.
Wavefield extrapolation (WFE) multiple prediction typically operates in common shot domain, and is very effective to predict complex multiples such as.
Reverse-time migration (RTM) provides superior images in areas where there are steep salt flanks or other complex geologic structures. However, the high.
We present a case study of anisotropic model building and the resulting accuracy of event placement and improved image quality. Approximately 660 OCS.
Subsalt wave-equation based migration (WEM) scan is an effective way for subsalt velocity updating, and has become an industry standard practice; however,.
Compared to surface seismic, the increased complexity associated with seafloor seismic data (OBC) requires considerable attention to details if a.
The goal of repeat imaging (detailed studies of prospects as new information is available) using PSDM is to generate new locations for both development.
3-D prestack depth migration is the most time consuming part in velocity model building. To minimize the required iteration of depth migration, we first.
Wave equation (or wave field extrapolation) techniques have been used in industry for the past few years, with the purpose to improve the accuracy of 3D.