HARDIN Quality Geophysics

Reservoir Services

As Pre-Stack Inversion is considered, a Gather Conditioning (GC) processing sequence should be applied to the PSTM or PSDM gathers. This ensures gathers are in optimum condition for accurate calculation of VP, VS, and Density.

Gather Conditioning:

  • Attain PSTM Gathers (non-NMO) Can remove if necessary
  • Apply Radon - Remove / reduce constructive or destructive effects of multiples
  • Perform RMO (residual moveout correction) - additional flattening of reflectors
  • Perform Random Noise Attenuation - remove/reduce effects of random noise
  • Common Offset Balance - removes background AVO

Well Data:

  • Attain sonic and density well log from a reliable well - A synthetic trace is generated which is used to phase correct and correlate to seismic data.
  • After seismic data is corrected with respect to well, recovery of upper end of frequency spectrum to help increase resolution in gathers and recover high frequencies in longer offsets expanding offset range used for pre-stack inversion.
    Best to have 35� angle for 3rd-term inversion


  • Post-Stack Inversion - Produces Acoustic Impedance (AI) and discerns porosity. (lower impedance- higher porosity; higher impedance-lower porosity) helpful in carbonate and sandstone reservoirs
  • Pre-Stack Inversion - Produces VP, VS, and Density; from these ingredients, the following statistical calculations can be produced:
    • AI (Acoustic Impedance) - porosity
    • SI (Shear Impedance)
    • P-wave modulus
    • Poisson’s ratio - elasticity
    • Bulk modulus
    • Young’s modulus - brittleness / ductility
    • Shear modulus - rigidity
    • Lambda-rho - sands
    • Mu-rho - sands
Hardin International Processing, Inc.| 5300 Democracy Drive,| Suite 100 Plano, Texas 75024