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Full-waveform inversion (FWI) is a well-established technology for building high-resolution velocity models over complex areas. Conventional industry implementations of FWI typically use the acoustic approximation, which can break down in the presence of strong velocity contrasts where elastic effects in the recorded data cannot be ignored. These issues are well-known for salt and sub-salt areas, where elastic FWI becomes the recommended solution.

Significant subsurface imaging distortions are frequently encountered in intricate faulted structures below substantial gas accumulations in the overburden. The primary difficulty arises from the absorption of seismic energy by gas bodies, and the presence of complex velocity heterogeneities. In these settings, visco-acoustic Time-lag Full Waveform Inversion (Q-TLFWI) proves to be a valuable tool. Nevertheless, when these complex structures are not well illuminated by the diving waves, Q-TLFWI may struggle to rectify velocity errors. This paper demonstrates the application of Dynamic Resolution Q-TLFWI (DR-Q-TLFWI) for a typical narrow-azimuth streamer survey in offshore Indonesia.

In shallow water environments the presence of a hard water-bottom and near-surface geological complexities can give rise to strong guided-waves and other elastic effects in the recorded data. These effects can pose challenges for conventional full-waveform inversion (FWI) based on acoustic approximations, leading to dedicated workflows involving more robust cost functions. Nevertheless, accurate modelling of shallow heterogeneities and strong contrasts using an elastic engine is expected to yield improved inversion results.

Since the discovery of pre-salt oil fields offshore Brazil two decades ago, the Santos Basin has transitioned from an exploratory to a development phase. This requires a more comprehensive understanding of the reservoir physical properties. This study aims to demonstrate, on one of the biggest Brazilian oil fields, how five years of technological evolution for OBN processing can improve our understanding of the pre-salt reservoir. The Tupi producing field presents various imaging challenges due to its thick and stratified salt and complex pre-salt layer. The latest technologies, such as elastic Time-Lag FWI, RTM angle gathers using spherical binning and internal multiple attenuation, provide a more accurate velocity model, as well as better fault definition and AVA response. The impact on reservoir-based inversion of the Vp/Vs ratio shows decreased uncertainty at the target level.

In an exclusive interview with Frontier Energy Network, Emmanuel Nformi, Viridien’s Business Development Manager, Sub-Saharan Africa, Earth Data, and Samuel Essoh, Geoscience Director, PETROCI, spoke about the relationship forged with Côte d’Ivoire’s General Directorate of Hydrocarbons (DGH) and NOC, PETROCI Holding (PETROCI) since 1999 and the mutual benefits gained.

This paper demonstrates how generative artificial intelligence (AI) enhances geoscientific document processing by improving text analysis, table extraction, and figure classification.

This paper highlights recent progress and breakthroughs in land FWI with two examples from the Sultanate of Oman (one from the north and one from the south).

With a new name and its guiding vision to “see things differently”, Viridien (formerly CGG) focuses on human ingenuity to usher in a bright future across multiple sectors.

Recent discoveries in Namibia’s Orange Basin have raised industry expectations that a similar level of success could be replicated in its conjugate margin, Uruguay. Still considered as a frontier basin, the Uruguay deepwater has similar geological elements at basin scale and unique aspects at prospect scale that could help to achieve exploration success at Cretaceous stratigraphic levels.