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 application of full-waveform inversion (FWI) to bring high resolution to the velocity model is becoming a standard approach in the velocity.
The TGS Gigante project is comprised of 188,497 km of 2D seismic data acquired in 2016 and primarily covering the offshore Mexican side of the Gulf of.
By the end of 2018 TGS will have acquired a total of 45,000 km2 of high resolution 3D seismic across the Møre and Vøring Basins in the Norwegian Sea. This.
Clari-Fi™ is a broadband processing package which includes denoising, deghosting, designature and inverse-Q. A multi-domain denoising process attenuates.
TGS acquired a high resolution multi-client 3D seismic survey over Blocks 35, 36 and 37 in the Kwanza Basin offshore Angola. A 3D Kirchhoff and Reverse.
Volatile hydrocarbon prices are driving major changes in the industry. Companies are establishing new economic baselines and new criteria for evaluating.
The Hoop Basin was named after Der Hoop, a ship belonging to one of the great Arctic explorers, William Barents. Meaning ’hope’ in his native Dutch, this.
The Hoop Fault Complex area of the Barents Sea has seen great exploration success lately. The area offers a condensed Paleozoic and Mesozoic succession.
The first regionally extensive long offset 2D seismic program has been acquired in the slope and deepwater regions of the Labrador Sea, offshore Canada..
TGS' new regional 2D long-offset seismic survey of the Danish sector employs innovative processing techniques already proven in the North Sea and around.
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.
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.
Broadband seismic data is data that is rich in both low and high frequencies. High frequencies increase temporal resolution, and low frequencies reduce.
Innovative uses of seabed seismic technology will help operators glean billions from new and mature fields. High-potential returns with low risk and lower.
n the last decade and more, shale gas resources have emerged as a viable energy source. This became possible after the Mississippian Barnett Shale in the.
Gravity coring and dredging has been used to obtain extensive seabed sampling of escarpments and potential hydrocarbon seep sites offshore Greenland in.
Conventional migration tools have been implemented by the application of adjoint operators. Under simple circumstances this approach provides satisfactory.
Wide azimuth (WAZ) has been established as an indispensable seismic acquisition and processing methodology for exploration and development objectives..
In some of the newly explored areas around the world, 3D seismic surveys may not be available. Assessment of the exploration potential and in some cases,.
The frequency content and the temporal resolution of marine seismic data acquired using conventional constant-depth streamer is affected by the.
Seismic exploration of the Norwegian Barents Sea began over thirty years ago, but the acquisition of 3-D surveys have only commenced in recent years. The.
Innovative uses of seabed seismic technology can help operators glean billions from new and mature fields. High potential returns with low risk and lower.
Basin formation temperatures are an important consideration in oil and gas exploration and development because temperature controls the rates of chemical.
The Santos Basin, offshore Brazil, is a geophysically challenging area to image due to the presence of evaporite sequence layers, carbonate layers and.
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 –.
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.
The structural style of the African Atlantic margin shows significant differences between the passive rifted Northwest African Atlantic Margin (offshore.
Wide azimuth seismic surveying is firmly established as a key element in subsalt exploration and production in the Gulf of Mexico. The challenge now.
The Baffin Bay area offshore northwest Greenland represents a vast frontier exploration province. The aim of this work has been to create a new structural.
Due to the accuracy of the Reverse Time Migration (RTM) algorithm, RTM angle gathers show more coherent and correct moveout subsalt events than Kirchhoff.
As an alternative to the conventional high-resolution Radon transform, we propose a time-domain approach to transform a gather of pre-stack seismic data.
The Liberian basin comprises offshore Liberia and Sierra Leone. Details of the regional structure and petroleum prospectivity of this frontier margin have.
Lower frequency energy in the source wavelet is more likely to penetrate through the basalt than higher frequencies as it is less attenuated by intrinsic.
TGS has vast seismic experience in the Asia-Pacific region, including acquisition and advanced time and depth processing. Here we present a case study of.
We present a case study of enhanced imaging of wideazimuth data from the Gulf of Mexico utilizing recent technologies; and we discuss the resulting.
We have developed a new methodology for predicting and removing multiples in the postmigration depth domain based on wavefield extrapolation and.
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.
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.
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.
Creating an angle gather is a conceptually simple process of plotting reflection amplitudes along the angle. Reflection or opening angle can be directly.
A new methodology for building salt velocity models is proposed that allows effective testing of different salt interpretation scenarios. In this.
This paper examines how the understanding of the prospectivity of the Liberia-Sierra Leone Basin has developed over the last 40 years largely due to.
A velocity anomaly zone with high contrasts and small wave length variations is often a challenge for conventional depth imaging. It requires model.
We present a case study that uses different methods of addressing a sharp velocity contrast across a major fault boundary in the southwestern Barents Sea..
Reverse Time Migration (RTM) based Delayed Imaging Time (DIT) scans have been used routinely in production to update velocity models in subsalt or low.
In 2009 TGS acquired 2,947 km of 2D long-offset multi-client data in the Atlantic Margin across the far northeastern part of the Faroe-Shetland Basin.
Over the past 10 years TGS has built up a substantial geophysical database offshore Greenland. This includes over 64,000km of 2D seismic, much of which.
The sedimentary basins in the Baffin Sea, Davies Strait and Labrador Sea are surrounded by old continents consisting of 2.4 to 3.6 bill year Proterozoic.
In 2009 TGS acquired 2,770 km2 of multi-client seismic data in the southwestern Barents Sea across the Hoop Fault Complex covering acreage nominated in.
The source rock for the hydrocarbons in the Upper Jurassic, Cretaceous, and Tertiary reservoirs in the eastern Gulf of Mexico is postulated to be Upper.
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.
The long history of imaging in this area will be reviewed. Incremental improvements in data quality and interpretability will be shown. Processing efforts.
The Benin Ultradeep seismic survey was acquired by TGS in 2009. 2D migrated seismic data shows the boundary between oceanic and stretched continental.
Chukchi and East Siberian Seas region represents one of the most remote and poorly studied areas of East Arctic. Wrangel Island is located between East.
Wrangel Arch represents the extensive (more, than 500 km) ~ E-W trending oshore basement high, separating the well-known shelf depressions: North and.
In January 2010 TGS completed the reprocessing of two regional long offset 2D multi-client seismic surveys in the Faroe-Shetland Basin (FSB). This.
A new salt velocity model building methodology is proposed which allows effective testing of different salt interpretation scenarios. In this methodology,.
We present a case study of an anisotropic prestack depth migration (APSDM) project which used high-resolution, shallow tomography and anisotropic model.
This study is based on the series of field works on Bel kov Island (Eastern Laptev Sea region) and Khatanga Bay area (Western Laptev Sea region). It is.
It is widely accepted that the key to successful sub-basalt imaging in the Atlantic Margin region is to generate as much low frequency energy as possible..
Based on a previous 2D seismic survey in offshore Sierra Leone and Liberia revealing the exploration potential of the margin, a 3D long offset survey in.
The Laptev Sea region is one of the remote and geologically complex areas of Russian Eastern Arctic. According to the existing seismic data, a number of.