Jason Data Calculations

FunctionMod™ is a model manipulation and arithmetic tool for working with the Jason™ suite data files. It is also used as the calculation engine in Largo and the more complicated functions in Map View.

Complex functions can be created, including results that cascade into other computations, and functions that branch to one or more sub-functions. FunctionMod also comes with a number of preset functions, and we are adding more all the time. Examples include mean, median, root mean square, sum, standard deviation, and over 50 others. Boolean logic and vector operations are supported.

The functions that you create and save are called transforms. Rather than referencing a particular data file, the transform references a type of file (e.g., a trace file with impedance traces, or a horizon file with time horizons). This makes the transform portable, and you simply assign the appropriate files when you want to execute the transform.

Application examples include:

  • Calculating lithology logs using Boolean logic such as “If the resistivity is greater than X and the Gamma Ray is less than Y, assign pay sand. If the Resistivity is less than X and the Gamma Ray is less than Y, assign wet sand. Otherwise assign shale.”
  • Calculating derived parameters such as Poisson's Ratio and Lame parameters from P-Impedance and S-Impedance following a RockTrace® Simultaneous AVA inversion.
  • Calculating mean and standard deviation volumes following a StatMod® geostatistical inversion.
  • Calculating porosity and lithology probability models from StatMod results.

Important features include:

  • Input can be a combination of property data, well logs, horizons, trend models, depth/time, sample interval, coordinates, or even single values.
  • Vertical range of data is selected via a time gate, solid model, well top pairs, or wherever data are available.
  • Different functions can be applied to different areas defined by solid model layers or well top pairs.
  • Complex functions can be created and set up to cascade into other computations.
GeoSoftware - Jason


Advanced technology in seismic inversion and reservoir characterization. Optimize well productivity, field development and reservoir management.
GeoSoftware - Software Support

Software Support

Our team of experts have years of collective experience in geoscience software. Find the resources you need to answer your questions. Visit our support portal to get the help you need.
GeoSoftware Support - Contact Support

Contact Support

Get support phone numbers and email addresses for your geographic region. Request software download credentials and assistance with setting up user ID/password. Our 300 experts in 17 countries stand ready to serve you.