Simultaneous Elastic Inversion
StratiSI is a stratigraphic 3D simultaneous elastic inversion. Multiple seismic angle stacks are simultaneously inverted to derive elastic attributes in a layered model composed of high-resolution micro-layers. The fine-layered stratigraphic grid framework provides improved resolution of thin beds and is the natural format for interpretation and integration into downstream reservoir applications.
StratiSI is part of the StrataVista seismic reservoir characterization platform.
A single stratigraphic micro-layer showing a channel feature extracted from the inversion volume. The attribute shown is P-Impedance. Cross-plotting P- and S-Impedance has been used to discriminate lithologies, highlighting the channel sands (red) and the shales (green).
- True 3D multi-trace inversion for Vp, Vs, density and layer thickness
- Inversion performed in stratigraphic framework
- Full Zoeppritz equation for accurate AVA modelling
- Extensive integrated GoCAD-based QC toolkit
- Controlled angle-dependent wavelets
- Wide range of constraints:
- Lateral and dip-consistent structural continuity
- Space-variant error corridors
- Auto-layered model building using seismic image
- Improved thin bed resolution
- Accurate lithology and fluid prediction with multiple elastic attributes
- Stratigraphic results facilitate interpretation
- Direct integration with reservoir model
The use of ultra-far offsets and large angles enables robust estimates of density and Vp, Vs with the simultaneous inversion. With this full set of elastic parameters, additional attributes can be derived to provide improved lithology and fluid discrimination such as the Shear and Bulk moduli.
In this reservoir (above), the inversion of ultra-far offsets has been used to characterize sand injection features with the Shear and Bulk moduli. The bulk modulus is sensitive to fluid and clearly shows the hydrocarbon in both the main reservoir interval and a steeply dipping sand injection feature (indicated by arrows). By contrast, the injection feature does not appear on the shear modulus section which is a lithology indicator.