Using the QI Stochastic Model Window

The QI Stochastic Model window is organized into several tabs.  

The following tabs are available in the QI Stochastic Model window:


The Trends tab allows you to open a trend file in the QI Stochastic Model window. 

See Loading a Trend File for more information.


In the Fluids tab, the individual fluids loaded from a trend file can be viewed and composite fluids added.

See Creating Fluid Composite for more information.


Lithology refers to the macroscopic nature of the mineral content, grain size, texture and colour of rocks. All lithologies (both reservoirs and non-reservoirs) defined in the loaded trend file will be displayed in the Lithologies tab.

See Creating Lithologies Composite for more information.


The Litho-Fluids tab allows you to combine the lithologies and fluids defined from the previous sections to create a lithofluid combination. This combination primarily consists of a reservoir, a non-reservoir (as a mixing component), and the fluid filling the pore spaces of the reservoir.

See Creating Litho-Fluids for more information.


In the Interfaces tab, the boundary between two different rock layers (reservoir, non-reservoir or any user-defined litho-fluid combination), each with their respective elastic properties can be generated for stochastic amplitude variation with offset (AVO) analysis, which is a variation in seismic reflection amplitude with a change in distance between the shot point and receiver (offset). 

See Creating Interfaces for more information.


The Probabilities tab displays the properties and frequencies of parameters available for custom crossplots. Information in the Probabilities tab cannot be altered manually. It is based on the determining factor and stochastic parameters set. 

See Using the Probabilities Tab for more information.

Reflectivity and Separability

The Reflectivities and Separability tabs in the QI Stochastic Model window display reflectivity and separability charts based on predetermined interfaces (with uncertainty), which are useful in AVO classifications. 

See Reflectivity and Separability for more information.

Litho-fluid Model

The Litho-fluid Model tab allows you to set the parameters necessary for stochastic modelling, which is used when there are various input parameters (each with an associated error or variation) and complex formulas to run them through. 

See Generating a Litho-fluid Model for more information.

Interface Model

The Interface Model tab allows you to set parameters to adjust the near/far angle (the intercept angle at the interface to calculate near/far interface properties) for stochastic modelling.

See Generating an Interface Model for more information.