Time-lapse (4D) seismic monitoring generally benefits from a dedicated co-processing where important inconsistencies between vintages are attenuated. We propose a joint formulation for least-squares migration (LSM) that further mitigates effects such as low repeatability and diverse data quality, by constraining the least-squares inversion with ...
Technical Content
Quantifying the effects of TTI in multiphysics analysis of electromagnetic data offshore Malaysia
Quantifying the effects of TTI in multiphysics analysis of electromagnetic data offshore Malaysia
Marine sediments are often electrically anisotropic at a scale that affects controlled source electromagnetic (CSEM) data. When the sedimentary sequence is steeply dipping, it is important to model the data using resistivity fields that follow the sedimentary bedding, which is called tilted transverse isotropy ...
Leveraging TLFWI and FWI Imaging to overcome geological complexities and acquisition challenges in onshore Mexico
Leveraging TLFWI and FWI Imaging to overcome geological complexities and acquisition challenges in onshore Mexico
In onshore southern Mexico, thick Mesozoic intervals, extensive salt, and over-pressured shale pose significant challenges for seismic imaging. Leveraging newly acquired data with longer offsets, higher fold, and improved low-frequency signal, we adopt a time-lag full-waveform inversion (TLFWI) driven workflow to resolve the complex ...
Tackling subsalt complexity with elastic FWI using long-offset, low-frequency sparse OBN data
Tackling subsalt complexity with elastic FWI using long-offset, low-frequency sparse OBN data
In recent years, full-waveform inversion (FWI) techniques have evolved significantly - from acoustic FWI (AFWI) that works surprisingly well in salt environments to the latest elastic FWI (EFWI) and high-frequency EFWI Imaging that provides unprecedented clarity in subsalt imaging - largely driven by rapid ...
Deblending of long-offset, low-frequency sparse OBN data under multiple types of interference
Deblending of long-offset, low-frequency sparse OBN data under multiple types of interference
Simultaneous source acquisition significantly enhances ocean bottom node (OBN) survey efficiency, but it also introduces blending noise contamination in continuous recordings. Deblending, which separates primary source signals from blended data, is a crucial step in preprocessing for both 3D and 4D imaging using conventional ...
Geomechanical Risk Assessment for CO₂ Storage in the North Sea’s Luna Site: A Seismic-Driven Coupled Compositional Flow and Geomechanics Approach
Geomechanical Risk Assessment for CO₂ Storage in the North Sea’s Luna Site: A Seismic-Driven Coupled Compositional Flow and Geomechanics Approach
A comprehensive assessment of geomechanical risks is essential for the success of geological carbon storage. Although the relationship between injection-induced pore pressure changes and rock failure is broadly understood in poromechanics, the challenge of characterizing and managing geomechanical hazards associated with subsurface CO₂ injection ...
Maximizing the value of the first time-lapse OBN data at Liza field with co-processing
Maximizing the value of the first time-lapse OBN data at Liza field with co-processing
In this case study, we present results from the first ocean bottom node (OBN) based 4D imaging at the Liza field, offshore Guyana. With two nominally repeated OBN surveys acquired within less than a year, we initially employed a parallel 3D processing flow to ...
Imaging the Delaware Fill Zone with ultra high-density data and high-frequency land FWI
Imaging the Delaware Fill Zone with ultra high-density data and high-frequency land FWI
An advanced imaging flow including 40 Hz full-waveform inversion (FWI), in conjunction with an industry-supported ultra-high-density survey provides a high-resolution FWI velocity model and FWI Image to resolve complexities related to the Cenozoic sedimentary fill in the Delaware Basin. The more accurate of the ...
Advancing subsalt imaging in the US Gulf: Operational and technical innovations in seismic data acquisition from the Laconia sparse OBN program
Advancing subsalt imaging in the US Gulf: Operational and technical innovations in seismic data acquisition from the Laconia sparse OBN program
The Laconia program marks a major advancement in the design and execution of long-offset, low-frequency (LOLF) ocean-bottom node (OBN) seismic acquisition programs for subsalt imaging in the U.S. Gulf. With more than 18,000 km²of source coverage and more than 8000 node locations, this multiphase ...