CGG has always been at the forefront of industrial High Performance Computing (HPC) architectures: we were operating vector supercomputers (Convex, Cray and NEC) in the early 1990s, and large parallel supercomputers (Convex SPP, IBM SP, Sgi Origin) by the end of that decade. At ...
Technical Content
Optimal transport full-waveform inversion: from theory to industrial applications with examples from the Sultanate of Oman
Optimal transport full-waveform inversion: from theory to industrial applications with examples from the Sultanate of Oman
The optimal transport problem was formulated more than 200 years ago to calculate the optimal way of transporting piles of sand. Due to the interesting properties of its solutions with respect to shifts between the compared distributions, optimal transport has recently been adapted to ...
Learnings from an FWI imaging study using 3D and 4D data over a postsalt field in Campos Basin
Learnings from an FWI imaging study using 3D and 4D data over a postsalt field in Campos Basin
Seismic images obtained through conventional migration methods have limitations as amplitude distortions and migration artifacts. To mitigate these limitations, we can generate FWI Images by computing the reflector-normal derivatives of the high-frequency FWI velocities. Given the resolution, accuracy, and geological consistency of the velocities ...
RTM 3D angle gathers for OBN data using an equal area spherical binning method
RTM 3D angle gathers for OBN data using an equal area spherical binning method
Compared with towed-streamer acquisitions, ocean bottom nodes (OBN) generally provide fuller-azimuth illumination of the subsurface, longer offsets, higher signal-to-noise ratio (S/N), and improved low frequencies. These advantages provide the necessary ingredients for two key elements of seismic exploration and monitoring: (i) full-waveform inversion (FWI) ...
Joint time-lapse full-waveform inversion with a time-lag cost function
Joint time-lapse full-waveform inversion with a time-lag cost function
Seismic time-lapse (4D) surveys have been widely used to quantitatively monitor the geophysical property changes within hydrocarbon reservoirs due to production effects. Full-waveform inversion (FWI), which has become one of the most reliable tools for velocity model building (VMB), is a natural technology choice ...
Paradigm shift: Recent advances in model building and imaging at Shenzi
Paradigm shift: Recent advances in model building and imaging at Shenzi
After many years of processing seismic streamer data acquired over the Shenzi field in deep-water Gulf of Mexico (GOM) with the best available technology, the workflows have remained highly interpretive, far from robust, often time-consuming, and ultimately proved inadequate for resolving the complexity of ...
Sim-source for 4D: Learnings from processing the first ISS OBN monitor survey at Atlantis
Sim-source for 4D: Learnings from processing the first ISS OBN monitor survey at Atlantis
Driven by the notion that blending noise may materially increase the background noise level and obscure the interpretation of weak time-lapse (4D) signals related to subtle reservoir changes, the industry has not yet seen any simultaneous-source (sim-source) surveys acquired for reservoir monitoring. Thus, whether ...
Shear-wave velocity update using PS reflection FWI for imaging beneath complex gas clouds
Shear-wave velocity update using PS reflection FWI for imaging beneath complex gas clouds
Shear wave velocity model building (S-wave VMB) is a critical and difficult processing step for converted wave imaging. Conventional S-wave VMB depends on PP-PS joint interpretation-based image registration and PP-PS joint tomography-based residual moveout flattening which have certain advantages and drawbacks. We introduce PS ...
FWI Imaging: Revealing the unprecedented resolution of seismic data
FWI Imaging: Revealing the unprecedented resolution of seismic data
Although the resolution of a seismic image is ultimately bound by the spatial and temporal sampling of the acquired seismic data, the seismic images obtained through conventional imaging methods normally fall far short of this limit. In addition to attenuation in the Earth, factors ...