Modern Seismic Reservoir Characterization

Leon Thomsen

This course summarizes the state-of-the-art of seismic reservoir characterization, using anisotropic seismic rock physics, and avoiding many of the outmoded assumptions of classical reservoir characterization.

Classical reservoir characterization typically assumes that the reservoir is elastically and hydraulically isotropic. However, most real reservoirs are actually anisotropic, and spatially heterogeneous (on many scales), so that core and/or log data are not representative of the larger reservoir volume.  Hence, the best means to physically characterize most real reservoirs, throughout their full volume, uses seismic data, acquired and interpreted anisotropically.

This course summarizes the state-of-the-art of seismic reservoir characterization, using anisotropic seismic rock physics.

Topics include:

  • Context
  • Physical principles
  • Anisotropy
  • Lithology
  • Geomechanics
  • Fluids
  • Pore pressure
  • Anisotropic AVO
  • Fractures
  • Permeability

Length of Course

16 hours

Intended Audience

Advanced Level   

Pre-requisites (Knowledge/Experience/Education Required): 

Knowledge of classical reservoir characterization

Course Description

This course summarizes the state-of-the-art of seismic reservoir characterization, using anisotropic seismic rock physics, and avoiding many of the outmoded assumptions of classical reservoir characterization. Applications address both conventional and unconventional reservoirs. Numerous in-class exercises are included.

Classical reservoir characterization typically assumes that the reservoir is elastically and hydraulically isotropic, and may be adequately analyzed using core and/or log data. However, most real reservoirs are elastically and hydraulically anisotropic, and spatially heterogeneous (on many scales), so that core and/or log data are not representative of the larger reservoir volume. This applies to both conventional and unconventional reservoirs. Hence, the best means to physically characterize most real reservoirs, throughout their volume, uses seismic data, acquired and interpreted anisotropically.

This course summarizes the state-of-the-art of seismic reservoir characterization, using anisotropic seismic rock physics. The course normally requires 16 hours of instruction, and includes numerous classroom exercises.

Topics include:

  • Context: A world with excess supply of oil, and low demand. The shale revolution. Hubbert’s extended Peak.
  • Physical principles: Aliased data. Inhomogeneous formations. Friendly multiples. Spatial resolution
  • Introduction to Anisotropy: Weak. Polar. Azimuthal. Shear wave splitting.
  • Lithology: Shale content from anisotropy itself.
  • Geomechanics: Without Poisson’s ratio or Young’s modulus, since these are isotropic concepts.
  • Fluids: Logical error in Gassmann poroelasticity.
  • Pore pressure: Subsurface fluid compartments. Anisotropic velocities for calibration.
  • Anisotropic AVO: Including the anisotropic term in the AVO gradient, a first-order effect!
  • Fractures: No penny-shaped cracks. Multiple fracture-sets.
  • Permeability: 4D gives the best seismic measure. Impermeable barriers.

Learner Outcomes:

Upon completion of this course, participants will:

  • realize that many of the assumptions of conventional reservoir characterization do not apply to the Real World
  • understand the basic elements of anisotropic seismics
  • be able to implement that understanding to estimate lithology, pore pressure fractures, and permeability from seismic data, with appropriate caveats
  • be able to apply post-Gassmann fluids estimation
  • be able to forward-model anisotropic AVO, and to find the missing parameter from the data.

Instructor Biography

Leon Thomsen