PS-wave azimuthal anisotropy: benefits for fractured reservoir management

Fractured reservoirs have been encountered worldwide and in general they are profitably produced, however<br>it is safe to say that none of them have been depleted efficiently. As the seismic industry focuses more on<br>production and development it is becoming more important to recognize the presence of fractures for optimal<br>reservoir management. Fractures can significantly influence the behavior of reservoir porosity and<br>permeability, resulting in numerous dry wells and higher production costs. A key strategy for fractured<br>reservoir management is a quantitative description of the geology, geophysics and petrophysical attributes.<br>3D converted-wave (PS-wave) surveys provide complimentary surface-seismic information to help identify<br>fracture properties early in the production history of a reservoir. Based on azimuthal anisotropy<br>measurements, PS-waves indicate fracture density and strike, and because of their asymmetry they are also<br>sensitive to fracture dip. These large-scale properties will be critical for solving specific production problems<br>associated with different fractured reservoir types, and could improve reservoir modeling: production-history<br>matching, and fluid-flow simulation. From an economic point of view, if multicomponent surveys prevent a<br>small fraction of unproductive wells, then they are worth the expense.