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This study focuses on mapping the lateral and vertical extent of high-quality reservoir sandstone units within the Late Jurassic Fulmar Formation, adjacent to salt interpod walls within the Shaw Field, UKCS. An integrated approach, which combined biostratigraphy, petrography, electrofacies, image log analysis and seismic interpretation, was used to understand the link between salt tectonics, sediment provenance, depositional environment, and reservoir quality.

Mohns Ridge is currently the subject of much interest owing to the occurrence of hydrothermal vent fields and critical metal-bearing seafloor massive sulphide (SMS) deposits along this segment of the ultraslow-spreading Arctic Mid-Ocean Ridge. To target where potentially mineable SMS deposits may form or have formed, there is a need to clearly image surface morphology and subsurface permeability, fluid zones and heat sources, along with documenting ecosystems and environmental baselines.

Multi-dimensional deconvolution (MDD) is an attractive method to remove free-surface multiples for OBN datasets. Multi-dimensional implementations are able to produce accurate multiple models in areas of structurally complex reflectivity. For most OBN acquisitions, the receiver density is not sufficient for receiver-side MDD. Consequently, source-side methods have been introduced to take advantage of the often denser source sampling.

Acoustic full-waveform inversion (FWI) is widely employed to produce high-resolution subsurface models, especially for the P-wave velocity. However, more complex geological challenges, such as shallow chalk and salt, generate strong impedance contrasts that exhibit elastic effects, causing acoustic approximations to struggle. In parts of the Southern North Sea, fast shallow chalk outcrops at the water bottom and Zechstein salt geometries sit above target intervals, both severely challenging velocity model building and imaging. This shallow-water case study uses short-offset, dual-azimuth, towed-streamer data where the near-surface geological environment and maximum acquired offset limit the diving-wave penetration.

A good estimation of velocity anisotropy is important in a pre-stack depth migration project in order to obtain proper focusing and accurate depthing of the seismic image. Considering that the velocity along the bedding is expected to be faster than across the bedding, the anisotropy parameter epsilon ( Thomsen, 1986 ) is typically positive. We present an example of shallow water imaging from offshore Suriname, in which using negative epsilon was found necessary in order to achieve both seismic well tie and flat pre-stack depth migration image gathers. From well information, the negative anisotropy correlates well with the mostly unconsolidated sand layers.

Marine vibrator sources offer the ability to emit a fully customisable and accurately repeatable sweep signature. Resulting peak amplitude levels are much lower than for airguns, making marine vibrators potentially preferable for the welfare of marine life. While the highly repeatable nature of the signal may be attractive for time-lapse applications, it must be considered alongside other time-lapse repeatability factors such as source positioning.

A multi-disciplinary project is presented utilizing data from the CGG archives and re-purposing them for porphyry copper deposit exploration. we reprocess the data, interpret and combine the results and place them within a holistic mineral systems framework to derive new exploration insights and demonstrate an effective methodology for search-space elimination and targeting.

The top basement surface of the Patch Bank Ridge offers distinct morphologies that are studied in detail. We use the seismically interpreted top basement surface as our digital elevation model to analyze geomorphology and structure and discuss differences and timing of the development of top basement geomorphology based on the age of onlapping and overlying stratigraphy. Three characteristic morphologies are identified, where the oldest is a rugose morphology on its flanks likely developed during the Devonian.

The Early Cretaceous sands on the Måløy slope constitute as reservoir for many oil and gas discoveries as seen in the Duva field and Hamlet and Ofelia discoveries. These sands have been deposited in submarine channels and fans, fed by material derived from the Norwegian mainland, through a series of shelf-edge canyons, established in the Late Jurassic.