Technical Library

  • Quantitative interpretation sensitivity to angle and frequency-dependent pre-stack time shift, amplitude and phase perturbations

    Author: Matthew Whaley, Cyrille Reiser, Andrew Long
    First Break - 3 November 2017

    View summary

    Matthew Whaley, Cyrille Reiser and Andrew Long present a modelling study to quantify how angle-dependent time shifts, angle-dependent frequency variations, or frequency-dependent phase errors can impact the recovery of elastic impedance attributes using pre-stack simultaneous seismic inversion.

  • Project highlights new prospectivity in the Santos Basin

    E&P Daily News - 27 September 2017

    View summary

    The rejuvenated Santos Vision regional dataset is ideal for pre-salt exploration in Brazil. This new product covers an area of 35 000 sq. km and has been reprocessed with our most advanced imaging solutions, including least-squares, RTM and Q-Kirchhoff.

  • Reducing FWI dependence on long offsets for deeper velocity model updates

    E&P Daily News - 26 September 2017

    View summary

    Reflections rather than diving waves and refractions push FWI deeper

  • Rapid interactive RTM scenario testing improves image quality beneath complex salt

    E&P Daily News - 25 September 2017

    View summary

    A new workflow assesses seismic image quality throughout the velocity model-building process.

  • Strategies for High Resolution Towed Streamer Acquisition and Imaging of Shallow Targets

    Author: Martin Widmaier, David O’Dowd, Carine Delarue
    SEG - 1 September 2017

    View summary

    The challenging combination of shallow water and shallow exploration targets in larger parts of the Barents Sea cannot be sufficiently addressed by the application of conventional marine seismic acquisition and imaging techniques. High resolution data, proper spatial sampling, as well as near offset/near angle information are key elements for imaging and quantitative interpretation. We first discuss several existing acquisition and imaging technologies that have been applied in the area, including standard towed streamer surveys, p-cable, and imaging with separated wavefields. We then introduce novel acquisition concepts. The innovative combination of high density seismic and wider towing of sources can be a cost-effective approach to acquire high quality seismic data with significantly improved near offset coverage and denser spatial sampling for shallow imaging. These configurations can be tuned such that both shallow and deeper targets are optimally imaged.

  • Sea surface source-side static optimization for 4D seismic

    Author: Simon Barnes, Paul Lecocq, Stephane Perrier, Mick Igoe
    SEG - 1 September 2017

    View summary

    Management of producing fields can be enhanced by effective seismic reservoir monitoring. Improved repeatability of 4D monitor surveys can be achieved by applying deghosting and datuming via seismic wavefield separation. By also correcting for the variable distance of the source above the seabed caused by the sea state will increase 4D repeatability further.

  • High-performance computing for seismic imaging; from shoestrings to the cloud

    Author: Sverre Brandsberg-Dahl
    SEG - 1 September 2017

    View summary

  • Global 3D acoustic FWI using sparse model parameterization

    Author: Debanjan Datta, Mrinal K. Sen, Scott Morton, Faqi Liu
    SEG - 1 September 2017

    View summary

    Estimating a starting velocity model for Full Waveform Inversion can be challenging. It requires several passes of migration velocity analysis to obtain a model accurate enough to prevent cycle skipping. We present an alternative approach to estimate a 3D starting model using a global optimization method called Very Fast Simulated Annealing. To constrain the optimization problem with a large number of unknowns, we parameterize the 3D model with surfaces and velocities surrounding them and solve for the optimal parameters. The final estimated model from VFSA serves as a starting model for FWI. We demonstrate the effectiveness by comparing FWI results along a few 2D lines from the 3D model. The proposed method is largely automated and reduces numerous man hours required to build a starting model. We apply our proposed method to one toy model and one complex synthetic model.In both cases, we were able to obtain acceptable results. Use of VFSA with a sparse parameterization method makes our 3D global inversion a practical tool.

  • Total hydrocarbon volume in place: improved reservoir characterization from integration of towed-streamer EM and dual-sensor broadband seismic data

    Author: Zhijun Du, Ghazwan Namo, Joshua May, Cyrille Reiser, Jonathan Midgley
    First Break - 1 September 2017

    View summary

    The authors present a geophysical reservoir characterization workflow that seeks to integrate elastic and electric attributes derived from inversion of seismic and CSEM data.

  • Application of a Full 3-D Designature Solution to a Wide Azimuth Survey

    Author: Jack Kinkead, Jon Burren
    SEG - 1 September 2017

    View summary

    The current drive within the industry is towards a “Full Bandwidth” solution for seismic imaging coupled with acquisition solutions such as “Multi-Azimuth”, “Wide-Azimuth” and “Full-Azimuth”. Additionally, changes in source array geometry and multi-sensor receivers have also been employed. The proper processing of these types of data requires that special attention is given to how the wave field is produced, its propagation through the earth and finally how it is being captured. Of particular interest, and in order of their relative impact to the wave field, are:

    •  Surface ghost effects
    •  Source array effects
    •  Receiver array effects
    •  Earth effects

    This paper will focus on the ghost and source array effects and the results achieved when they are handled properly.