Technical Library

Gravity coring and dredging has been used to obtain extensive seabed sampling of escarpments and potential hydrocarbon seep sites offshore Greenland in the northeast Atlantic. Sampling of sub...

Conventional seismic data processing, whether pre-stack data conditioning or migration, is designed with the theory of P-wave reflected energy in mind for travel paths involving only a single...

Conventional migration tools have been implemented by the application of adjoint operators. Under simple circumstances this approach provides satisfactory results. In situations where the overburden...

Wide azimuth (WAZ) has been established as an indispensable seismic acquisition and processing methodology for exploration and development objectives. This is especially relevant in the Gulf of...

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, even a critical well-drilling decision is...

The frequency content and the temporal resolution of marine seismic data acquired using conventional constant-depth streamer is affected by the interference from the reflections at the sea surface in...

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 design of these surveys is based on the...

Broadband seismic data are becoming increasingly common, with many different methods of producing a broader range of frequencies. Accurately recorded broadband frequencies are of particular use for...

The study addresses the hydrocarbon prospectivity of offshore Gabon with a particular focus on the South Gabon Basin based on detailed 3D PGS/DGH MegaSurvey seismic and well data interpretation. It...

PGS has recently completed deployment of the worlds first, and to this date only, full-solution deep-water PRM project in the Jubarte field in Brazil for Petrobras. The project includes a fully...

In October 2012 the Alvheim-Boa Field was surveyed as part of a North Sea acquisition campaign with the newly developed Towed Streamer EM System to provide resistivity estimates over a number of...

Conventional wave equation migration extrapolates upcoming boundary data generated from primary reflections to image the subsurface. In marine seismic data processing, sea surface related multiples...

This paper describes a new method for on-line evaluation and acceptance of seismic interference (SI). The project was split into three phases. The first phase utilized existing data with SI issues...

This paper describes how a large, 12,030 sq.km, exploration 3D seismic survey in the Great Australian Bight was designed in order to maximize the efficiency of the survey. The entire survey area was...

Viscoacoustic imaging in anisotropic media is achieved by tomographic estimation of the earth attenuation (Q model), and prestack wave equation migration. The proposed Q tomography algorithm uses...

3D angle domain common image gathers (ADCIGs) from reverse time migration (RTM) provide accurate representation of residual moveout in complex media, especially in the presence of salt. Thus,...

Reflection tomography is non-unique and a regularization term is usually added into its objective function as an additional constraint. The anisotropic Gaussian filter has been successfully employed...

Reverse time migration (RTM) imaging can have significant artifacts which are generated by back scattered and turning waves, where the source and receiver wavefields are in phase. This paper gives a...

The current approach for the quality control (QC) process of the swell noise filtering phase carries significant drawbacks. This abstract investigates the use of statistical techniques to improve the...

The four offshore basins of Namibia are highly underexplored despite one of these basins containing the large undeveloped Kudu gas field. Substantial discoveries elsewhere on both sides of the South...

Separated wavefield imaging helps to improve the subsurface illumination when the towed streamer acquisition geometry is properly designed. Compared to the conventional imaging, which uses a full...

A modified one-way equation pre-stack depth migration of up-going and down-going pressure wavefields was applied to two datasets derived from 3D towed dual-sensor streamer data in offshore Australia...

An innovative 3D towed streamer project in offshore Gabon used a dual-vessel continuous long offset streamer configuration to acquire 0-12 km offsets with ten dual-sensor streamers. Streamer control...

There is ever increasing interest in exploring pre-salt provinces across the South Atlantic Conjugate Margin The 2006 discovery of the Lula (Tupi) field in the Brazil Santos Basin and more recent...

The underexplored offshore deepwater basins of Angola hold tremendous potential for hydrocarbons. These basins have marked similarities with the prolific hydrocarbon producing region of the Brazilian...

We present a workflow to assess the risk of excessive sound exposure on marine mammals based on forward modelling of the far-field signatures from airgun arrays. The employed physical model takes...

In October 2012, several of previously known oil and gas fields, located in the North Sea, were surveyed with the newly developed Towed Streamer EM System. This paper discusses a first result of a...

In marine seismic imaging, acquisition related footprints often contaminate the shallow parts of the subsurface. A main challenge today is to find new acquisition and imaging techniques in order to...

In many seismic processing applications, such as filtering and interpolation, the input data is partitioned into small overlapping blocks that are processed separately and then merged to construct...

Multi-azimuth data acquisition has shown benefits in noise reduction and structure illumination, which leads generally to improved seismic images. However the current time processing, which is based...

The recently completed Congo regional seismic survey shows regional scale features in high detail. Individual channel systems have been recognized and exploited but now the regional scale extent of...

The imaging condition needs special attention in imaging of separated wavefields because of the increased complexity of the source wavefield. Starting from reciprocity relations and using...