Carbonate Reservoirs - Solutions
Challenge

A significant share of the world’s oil and gas reserves are held in carbonates and in particular in the Middle East. Carbonates may be highly heterogeneous at different scales from micro to kilometer. They present different types of heterogeneities due to diagenesis, depositional environment changes, structural history with the development of karst, vuggy, diagenetic facies and fractures which can play a role in the fluid pathways. Characterization and evaluation of carbonate reservoir properties is a multi-disciplinary effort, from core analysis and laboratory measurements to seismic and drilling techniques. Seismic expression of carbonate reservoirs depend on the play type context (reef, buildup, clinoform margin, etc). The determination of reservoir properties is instrumental for production optimization of infill drilling, horizontal drilling, and advanced fracturing.

 

RSI Solutions

By combining pre-stack and post-stack workflows we have developed an extremely powerful method to discriminate between ‘structural’ macro heterogeneities (e.g. fractures, karst) and formation properties (lateral variation of carbonate facies, diagenesis geometry, matrix porosity):

  • Post Stack workflow including:
    • Developing rock physics models to calibrate rock properties at well control data points (iMOSS)
    • Data conditioning (AVATAR)
    • Attribute Extraction & Calibration at well control (iMOSS)
    • Seismic Facies Analysis (ATTRIB3D)
    • Kohonen self-organizing neural network facies classifications (LITHANN)
    • Automatic Fault Extraction (AFE)
    • Inelastic seismic attributes (Q Factor)
  • Pre-stack workflow including in addition to the above:
    • Elastic Inversion (IFP)
    • Azimuthal AVO inversion (AVOZ)
  • Visualization and joint interpretation using several data mining techniques and latest visualization techniques (e.g. TransForm, SKUA)
  • Multi-attribute geological and seismic stratigraphic interpretation of reservoir heterogeneities and rock properties integrating production data and core analysis information.
  • WISE-Carbonate: For offshore fields having CSEM, this is a unique technology to integrate CSEM with seismic and wells.