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Over the years Shenzi field in deep-water Gulf of Mexico became a test bed for evaluation of new seismic acquisition and processing technologies. These include 3D narrow azimuth streamer data 3D-rich azimuth streamer data and recently 3D OBN data (Mifflin et al 2021). On the processing side many types of processing techniques were used to image the various data types recorded over Shenzi field from 3D ray-based Kirchhoff summation PSDM to Acoustic RTM PSDM and Acoustic FWI imaging. In the work presented here we demonstrate the advantages of Full Elastic imaging using the OBN dataset acquired by Woodside Energy in 2019 to better image the sub-salt field.

Data management has become a critical component of oil and gas exploration. The industry has spent years collecting storing analysing and interpretating subsurface data. This data is invaluable for making informed decisions on where to explore for hydrocarbons but properly managing subsurface data presents a multitude of challenges each of which impacts on the quality accessibility and utility of this crucial resource. In this article we explore the challenges associated with data management and review solutions for overcoming them.

The resistance of low-frequency seismic energy to scattering and absorption and its resulting ability to be recorded over long ray paths through attenuating media is well established. This relative resistance to scattering and attenuation makes it vital for capturing information with depth and offset both for model-building and illumination. There is likely to be no better example of this than modern long-offset OBN (ocean bottom node) surveys of the Gulf of Mexico – however the importance of high-quality low frequencies in unravelling imaging challenges below complex overburden such as shallow gas carbonates salt and volcanics is well documented. Consequently interest in recording low frequencies in the field extends beyond OBN surveys to include single-vessel and multi-vessel towed-streamer designs. We have seen strong focus on designing sources that produce rich low frequencies over the last decade as a result.

The article presents a framework designed for standardized cross-platform benchmarking of seismic imaging kernels. This framework aims to standardise the benchmarking process providing reference implementations for various architectures and enabling reproducible experiments. The system uses GitHub Actions for automation a development cluster composed of different computer architectures and on-demand runners on AWS. This setup allows for easy comparison of different methods hardware while also enabling the integration of more tools and servers. Preliminary results are presented for 3D isotropic acoustic and Fletcher Du Fowler TTI benchmarks using Giga-points per second (GPts/s) as a performance unit providing more practical insights compared to the standard FLOPS (Floating Point Operations Per Second) metric.

In the Austral segment of the South Atlantic the conjugate margins of Southern Brazil/Uruguay/Argentina and Namibia/South Africa have comparable geomorphological elements. Recent play-opening light oil discoveries (Venus Graff and Jonker) in deep-water Namibia have increased exploration interest in the whole Austral South Atlantic margin de-risking outboard stratigraphic plays and providing analogues for conjugate margin exploration.

The NOAKA OBN survey was acquired in late 2021 and covers an area of approximately 293 km2 (receiver patch size) it was acquired and processed with the objective of creating a dataset suitable for further field appraisal and development. Targets are situated in the Frigg formation and in Jurassic sandstones characterised by thin often faulted layers. These are overlain by younger sediments that can create distortions in the deeper sediments. After a preprocessing sequence going from deblending through to up-down deconvolution data were binned directly to the common offset azimuth domain and weighted prior to migration to maximize spatial resolution. Diving wave and reflection dynamic matching full-waveform inversion (FWI) combined with bespoke data conditioning designed to mitigate the effect of guided waves in FWI successfully identified fast geobodies in the shallow section. The final imaging benefited from the use of Q Kirchhoff pre-stack depth migration.

With more and more surveys utilizing FWI for high quality velocity models there is a need for additional low frequency energy beyond standard marine air gun arrays. The Gemini source is a novel solution to generating more low frequency energy for FWI while maintaining sufficient high frequency energy for typical processing and imaging workflows. This paper will give a brief history of the source and show data acquired in the Engagement 1 sparse OBN survey directly comparable to standard air gun arrays. The OBN data will be shown both in time domain wavelets and also imaged. The source is also significantly more environmentally friendly than typical air gun arrays. At 800Hz Gemini is more than 32dB below other sources which greatly reduces the risks and harm to marine mammals. A recent survey used the Gemini source as a primary source for the survey and operational efficiency will also be shown.

In this presentation a new single station rotational seismic sensor is introduced. The new sensor enables simultaneous rotational and translational sensing in three orthogonal axes representing 6 component (or 6C) measurements.

Data examples and early results from an offshore field trial are presented where the new sensor has been deployed in an ocean bottom node (OBN). Data from the new sensor are compared to reference data from adjacent conventional ocean bottom nodes containing standard 3C geophones.

Our findings are that the new sensor is fully deployable in an OBN setting and provides results consistent with reference data obtained by conventional nodes. These capabilities in a single station sensor also means there is potential for significant efficiency gains in OBN acquisition.

Channel system development in the Northeast Atlantic during the late Paleocene to early Eocene gives insight into uplift and erosion at the time of widespread break-up magmatism. During this time period the rapid uplift of the Shetland Platform led to erosion and the development of drainage systems surrounding the platform. Previously interpreted drainage systems are understood to have formed in non-marine and continental shelf environments. In this study we show that a drainage system also formed to the north of the Shetland Platform towards the Møre Basin. The geometry and location of the drainage system indicates that it formed in a submarine environment. Additionally we find a large dome (c. 1200 km²) immediately to the north of the channel system which is underlain by a sill complex. We name this structure the Jolnir Dome.