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This paper reviews the benefits of using “high-end new-generation” de-noising tools on a broadband single-source single-sensor Wide Azimuth survey acquired in Kuwait. A processing pilot has been conducted in a very challenging area containing agricultural and industrial zones, as well as various natural and man-made obstructions, leading to large holes and irregularities in the acquisition. We show that the in-place solution is correctly recovering the emitted broadband signal, by doing a dedicated processing on highly noise contaminated elementary traces. Then, once properly de-noised, a 5D interpolation process can faithfully reconstruct a consistent high resolution image, from the shallow to the deeper part. Appropriate de-noising steps prior to the 5D interpolation is also crucial for further processing steps as demultiple, pre-stack time and depth imaging and reservoir characterization.

Internal multiples constitute a major challenge for imaging. Artefacts generated by incorrectly imaging internal multiples interfere with targets, affecting the interpretation and contaminating amplitude analyses in the reservoir. The Santos basin is a particularly challenging example of this problem because of the presence of stratified salt. We implemented a method recently proposed by Van der Neut and Wapenaar (2016) to attenuate internal multiples and successfully applied it to a data set from the Santos basin.

While full wave based velocity model building approaches have earned their stripes during the last decade, ray based approaches remain the working horse in industry. I review here first the successes and the limitations of both families of approaches. If it appears that ray based approaches suffer of limitations in complex media, others of their characteristics like the picking (often seen as a weakness) or the computation of Fréchet derivatives may also appear in practice as decisive advantages. I believe that these are points on which we should challenge and even inspire full wave approaches. By the end rather than opposing ray based and full wave approaches I review the various trends in terms of the combination of the tools and concepts which appear from my point of view as the most promising.

Deriving high-resolution velocity models in heavily faulted areas is challenging. This is further complicated by the presence of gas bodies at multiple depth levels. In case of a WAZ or FAZ dataset, azimuthal anisotropy effect can be significant, depending on the presence of a principal stress orientation. To address these challenges, orthorhombic full waveform inversion (Ort-FWI) approach has been used to recover a high-resolution velocity model, addressing lateral velocity variations across faults or due to gas bodies, while honoring the azimuthal velocity variations. We show how Ort-FWI produces a high-resolution velocity model that improves fault focusing and heals fault and gas shadow effects.

WAZ’s sparse spatial sampling tends to limit our ability to push for shallow higher resolution image. In the deepwater GOM, there is typically more than one WAZ survey available. However, direct Kirchhoff imaging from multiple data sets suffers poor swing cancellation. To mitigate this problem, we can combine multi-WAZ data and perform interpolation prior to Kirchhoff. Interpolation reduces migration swings but is often not perfect for complex structures and smears details. We propose to use preconditioned least-squares (LS) Kirchhoff to obtain a higher resolution image that can simultaneously benefit from dual-WAZ data sets and overcome the limitation of coarse sampling.

The world-class oil and gas fields of the Gippsland Basin, with original recoverable reserves of more than four billion barrels of oil and around ten trillion cubic feet of gas, were discovered following a 1962 2D seismic survey. Despite considerable exploration, it has long been known that unresolved seismic depth imaging issues have had a significant impact on data quality. As a consequence, the province probably has unrealised exploration potential, particularly in the deeper stratigraphic section. The basin-wide Gippsland ReGeneration reprocessing project by CGG has changed the paradigm and the basin is now seen as rejuvenated, with new exploration opportunities and significant upside potential.

Extended seismic bandwidths provided by broadband acquisitions (BroadSeis), improved illumination from wide-azimuth (WAZ) configurations and high spatial resolution made possible by dense acquisition techniques are all new technologies producing visually compelling imaging and reservoir results. In addition, application of the latest reservoir characterization tools and workflows on these data are bringing greater insight into the inner workings of petroleum reservoirs.

In this paper, we propose an SVD-based (singular value decomposition) shear noise attenuation method that relies on P to drive the algorithm allowing a good signal preservation on Z. Using a fast SVD kernel, this method is suitable for large datasets. We demonstrate the effectiveness of the proposed method on a dense wide azimuth 3D OBS shallow water acquisition involving 56,000 4-component nodes. The results prove the efficiency of the proposed method in removing shear noise with no damage to the signal.

This article reviews the status of hydrocarbon exploration and level of geological understanding in the Durban and Zululand Basins offshore South Africa and it provides clues and new ideas from seismic interpretation and observations of the latest CGG multi-client 2D shot in the area in 2014.