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Time-lapse (4D) inversions deal with changes in seismic amplitudes and travel-times. This analysis is performed on migrated seismic images, which represent the spatial and time-lapse variability of the medium’s reflectivity. 4D reservoir analysis methods such as inversion and warping need to follow the structure of the data. Since migration effectively rotates the wavelet so that it is normal to the imaged reflectors, the traditional 1D (vertical) convolutional approach, used in 4D inversions to date, does not honour this directivity. For this reason we recently introduced a wave equation based method which provides an effective platform for structurally image consistent reservoir analysis. This must be used in processes such as wavelet extraction, inversion, warping and 4D time-strain inversion. In this paper, we show a data example from the 4D Baobab, comparing warping results for time-shifts and time-strains with a 1D convolutional and the new image consistent warping approach.

The Banda Arc is of great interest to petroleum explorers because of abundant onshore and offshore oil and gas seeps and similarities with geologically contiguous Mesozoic and Cenozoic successions in Australia where numerous petroleum systems exist and have been exploited (the Mesozoic basins are collectively termed the “North West Shelf”). Exploration of the offshore Banda Arc has previously been limited because of water depths, remoteness and seismic imaging problems associated with a zone of deformation occurring between the fore-deeps and the Banda Sea. In cooperation with the Indonesian Directorate General of Oil and Gas (Migas) and the Timor Leste National Petroleum Authority (ANP), CGG has acquired four phases of multi-client seismic data around the Banda Arc; collectively, these surveys are known as the BandaSeis Project. The data has been acquired with CGG BroadSeis broadband technologies and processed in depth: the regional Phase III data is currently being processed and will not be discussed in this article.

The May edition of Oilfield Technology is freely and widely distributed at the EAGE conference. CGG paid to appear on the cover and also got to contribute an article on a topic of our choice. This was designed to reflect our current advertising and marketing messaging. The main topic is recent advances in subsalt technology. We made reference to BroadSeis, StagSeis, RTM, FWI, dip-constrained channel tomography, Brazil/GoM data library and geohazards.

We present a method for the quantitative assessment of the subsurface suitability of saline aquifer CO2 storage sites using a case study example from the Northern North Sea.

The play-opening giant discoveries of Baleine and Murene-1 (Calao) offshore Tano Basin have reinvigorated exploration in the Equatorial margin of Africa. The basin is geologically complex and has proven its unparalleled hydrocarbon potential. To further explore this basin, there is a need for high-end imaging to enhance the regional understanding and de-risk the full play potential. In 2024, Viridien merged and re-imaged a seamless and contiguous volume of CDI-23 3D PSDM multi-client seismic data over an area of 6,434 km2 offshore Tano Basin, Côte d’Ivoire. This will soon be added to another 9,747 km2 of data from the CDI-24 Phase I and Phase II multi-client programs. Here we take a quick look at the fast-track imaging of the CDI-23 survey extending over the shelf to the outer slope domain, enhancing our understanding of the basin.

There are a number of geophysical challenges when attempting to image the sub-surface in the Central North Sea. These consist of shallow anomalies, heavy multiple contamination and sharp velocity contrasts. With a combination of broadband data and CGG’s latest processing and imaging techniques, these challenges become significantly reduced.

The main area of hydrocarbon exploration in the Northern North Sea has been within pre- and syn-rift Jurassic sandstones. This is with the exception of chalk reservoirs in the Ekofisk field and Palaeogene sand reservoirs of the Frigg field. Now, with ignited interest in the Horda Platform, and particularly after the discovery of the Grosbeak and Skarfjell oilfields, attention has been directed towards the hydrocarbon potential within post-rift Cretaceous sands. The prospectivity of the Cretaceous sands was demonstrated more than three decades ago with the Agat discoveries.

We present the results from flying the FALCON-2 system over the R.J. Smith AGG test range at Kauring, West Australia.

To coincide with ADIPEC 2024 Karim Lassel discusses Viridien’s bold rebrand and its commitment to drive innovation for the energy industry.