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In this paper we present a new marine seismic acquisition technique initially developed to meet imaging challenges of the Loppa High in the Norwegian Barents Sea. Two seismic vessels operate in tandem; one streamer vessel towing a spread of deep, densely spaced streamers, and one source vessel towing two or more sources. The source vessel is positioned on top of the seismic spread. The unique configuration facilitates acquisition of zero-offset data. This, together with the fact that both negative and positive offsets are recorded, creates a unique illumination density of the subsurface. The solution is developed and tested in close cooperation between CGG and Lundin through a comprehensive modelling and field trial program involving a series of safety and mechanical tests and also a small 3D test survey. The result is high-resolution seismic images in the shallow and improved S/N in the deeper sections.

While significant progress has been made in CCUS over the last five years, the industrial and financial sectors need to see how projects are being effectively de-risked. By capitalizing on the latest technology advances and the integration of multidisciplinary skills and data, geoscience has a critical role to play in de-risking for CCUS development.

Each year the geoscience industry creates huge volumes of documents containing a wealth of knowledge which cannot be easily queried or extracted. Key to the successful extraction and transformation of data is an understanding of the nature of the data that exists within a corpus of files. For large datasets, it is time-consuming to manually open and review each document in turn. Therefore, in this article, we discuss how machine learning is used at CGG to classify documents in our automated pipeline and reduce project times significantly.

Based on an extensive 3D modelling study utilising full-wavefield Finite-Difference modelling and Full-Waveform Inversion (FWI) we demonstrate that the TopSeis/OBN hybrid acquisition acquired from May to August 2021 in the Nordkapp basin in the Barents Sea has the potential to image salt flanks and sedimentary details, given an accurate initial model in the shallow and a carefully designed deblending and FWI workflow. As a part of this we demonstrate that the large offsets and multi-azimuth recorded by the ocean bottom nodes are crucial to image the complex salt diapirism in the area including the steeply dipping flanks.

This article will mainly focus on the fracture/fault analysis of CGG’s multi-client 3D seismic data to highlight the potential flow pathways and contribution of excess formation water in unconventional lateral well development. By using CGG’s InsightEarth (FractureFaultSpark) software, major intra-formational and through-going formational faults were identified throughout the main development formations (Wolfcamp and Bone Spring). Through the identification of these lineaments, and the petrophysical analysis of the above and below formations (water saturation), risk maps are developed for the operators, allowing them to proactively and appropriately prepare for these features within their drilling and completion campaigns.

The near surface in the Middle East is characterized by the presence of very shallow fast carbonates and anhydrites interleaved by slow-velocity clastic layers, resulting in sharp velocity inversions. We present here examples from two case studies in the Sultanate of Oman using Multi-Wave Inversion to retrieve the near-surface velocity model.

Over the past 35 years, geothermal projects have been developed in Upper Rhine Graben (URG) to exploit deep geothermal energy. Below a couple of kilometers of sediment, the deep target consists of granitic basement, highly fractured and hydro-thermally altered, having a high reservoir potential. In order to better understand large scale faulting and ensure viability of future geothermal projects, 3D seismic survey are acquired in the French part of the URG during summer 2018. This paper will present how the most recent seismic imaging sequence is designed in order to first process the acquired data and then build a depth velocity model allowing accurate positioning of the faulting.

The Humbly Grove field is a unique example of an onshore UK field with two co-existing revenue streams; seasonal gas storage and enhanced oil recovery. As with other gas storage facilities, Humbly Grove operates under strict safety legislation. The license to operate is dependent on a robust safety case. This was developed with an integrated approach to reservoir monitoring and modeling which combines a range of geoscience expertise to understand the behavior and safe limits for gas storage. CGG's involvement since 2012 has included reservoir modelling and flow simulation as the Operator's subsurface team. Safety monitoring, contracted to Durham University, involved ground and satellite based sensing and geomechanics.

While full waveform inversion (FWI) has imposed itself as a privileged velocity model building tool in areas investigated by diving waves, it is still penalized by its sensitivity to cycle skipping. Among the various strategies proposed to mitigate the problem, optimal transport (OT) FWI appears as one of the most successful industrial solutions. In order to illustrate this status we review a set of marine and land applications of multi-dimensional (in data space, not to be confused with the velocity model dimensionality) OT-FWI. Compared to classical FWI, we confirm a relaxed sensitivity to cycle skipping with in addition an update that goes deeper in the model (areas investigated by reflections) and an improved structural consistency.