TopSeis is a radically new solution for seismic acquisition and imaging, developed through collaboration between an oil company and the service sector.
Technical Content
Unlocking the tectonic history offshore Southern Gabon with high resolution seismic, gravity and magnetics
Unlocking the tectonic history offshore Southern Gabon with high resolution seismic, gravity and magnetics
A recent 3D Broadseis survey was performed in the southern offshore area of Gabon, showing a wealth of detailed information in the seismic data. Understanding how these structures relate to the tectonic evolution of this basin requires the integration of the concurrently acquired gravity ...
Data-driven interferometry method to remove spatially aliased and non-linear surface waves
Data-driven interferometry method to remove spatially aliased and non-linear surface waves
We propose a data-driven interferometry technique to remove low frequency aliased and non-conical surface waves in cross-spread domain. Despite insufficient sampling of the constructive regions in the cross-spread domain, the proposed approach has been designed for effectively handling any kind of 3D sparse geometry ...
Extending the reach of FWI with reflection data: Potential and challenges
Extending the reach of FWI with reflection data: Potential and challenges
We present a Reflection FWI (RFWI) workflow to update the velocity model using the low-wavenumber component of the FWI gradient of reflection data. This is achieved by alternately using high-wavenumber and low-wavenumber components to update density and velocity models, respectively. With synthetic examples, we ...
Monitoring the quality of prestack broadband seismic data
Monitoring the quality of prestack broadband seismic data
Reservoir characterization methods require seismic data processed for this purpose. We propose a QC methodology for AVO and low frequency. We use a small set of attributes with which we identify signal preservation and pre-stack data consistency across the full data bandwidth. The methodology ...
Improving mini-basin and subsalt imaging with reflection full waveform inversion
Improving mini-basin and subsalt imaging with reflection full waveform inversion
Reflection-based full waveform inversion (RFWI) is increasingly used to recover long wavelengths of the background velocity model and provide updates that extend beyond the reach of diving waves. In our case study, we use an RFWI method that first updates the density using the ...
PS depth imaging to detect clastic reservoirs -- Vietnam's first 3D-4C OBC survey in the Cuu Long Basin
PS depth imaging to detect clastic reservoirs -- Vietnam's first 3D-4C OBC survey in the Cuu Long Basin
In this paper, we focus on how to use PS imaging to help detecting the reservoir in the clastic layers. PS data allows for imaging of these reservoir units that have poor P-wave but high PS-wave reflectivity and also for lithological discrimination via extracted ...
Flattening common image gathers after full waveform inversion: the challenge of anisotropy estimation
Flattening common image gathers after full waveform inversion: the challenge of anisotropy estimation
It is often observed that common image gathers computed after FWI are not flat. This is due to an improper anisotropy estimation. We propose a new joint reflections-diving rays tomography to estimate anisotropy prior to FWI. It aims at both flattening the common image ...
Least-squares Q migration: the path to improved seismic resolution and amplitude fidelity
Least-squares Q migration: the path to improved seismic resolution and amplitude fidelity
Standard prestack depth migration (PSDM), e.g., Kirchhoff/RTM, is by nature unable to fully recover the reflectivity with desired amplitude and resolution due to factors such as inhomogeneous subsurface illumination and irregular acquisition geometry. This shortcoming is well recognized by the imaging community and has ...