Search

Recent exploration activities within Paleocene and Eocene remobilized sands have proven the injectite play in the Northern Viking Graben (NVG). Wells targeting these sands have led to new discoveries such as Kveikje (2022) and Heisenberg (2023). This study proposes a robust methodology for detailed mapping of sand injectites by leveraging seismic attributes and integrating machine learning techniques, with a particular focus on the Eocene interval. By analyzing the responses from the seismic attributes at the location of the initial discoveries, we successfully identified other areas exhibiting similar characteristics, indicating the potential presence of prospective sand injectites.

Elastic full-waveform inversion (FWI) is now emerging as an industrial tool for the compressional velocity (Vp) model build, driven mainly by diving and reflected P waves. On the other hand, the inversion of S waves in elastic FWI to update shear velocity (Vs) models is more challenging due to the limitations of data acquisition and reduced sensitivity of surface seismic to Vs. In this paper, we propose a practical methodology for low-wavenumber Vs updates by elastic FWI, driven mainly by converted waves in multi-component ocean-bottom seismic data.

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.

Geomechanical screening of potential CO2 storage sites in deep geological formations presents a substantial challenge, particularly in tectonically active regions like offshore Sarawak. In this study, we collect existing logs and downhole stress and pressure measurements to construct 1D mechanical earth models for three strategically located wells in the field.

This case study demonstrates the collaborative advantages when an Operator and a Geoscience Contractor work collectively as part of a tailor-made Integrated Virtual Asset team, to solve complex subsurface challenges in a restricted time frame. The operating challenge was to de-risk a potential drilling candidate with a licence renewal decision pending. A poor seismic image of the key exploration prospect, caused by structural complexity above the reservoir interval, left significant uncertainty about the geological model and trap presence. Neither legacy nor contemporary re-processing of the seismic data had suitably resolved the target.

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.

Fracture characterisation is a key factor for reservoir production optimization. Velocity Variation with Azimuth (VVAz) and Amplitude Variation with Azimuth (AVAz) are the main technologies currently used in the industry for azimuthal anisotropy characterisation, whether it is fracture- or stress-induced, from PP seismic data. These two technologies have their respective strengths and limitations and are often used separately to predict the reservoir fracture networks. In this paper, a joint azimuthal velocity and amplitude inversion workflow is presented to characterise the fracture orientation and intensity of a Middle East offshore carbonate reservoir using a high density WAZ OBC 3D seismic survey.

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.