Multi-Attribute Geobodies
Understanding multiple attributes is essential when evaluating prospects, but it’s easy to be overwhelmed with an endless array of maps and sections. Indicator volumes and geobodies are are great way to reduce complexity and quickly highlight potential areas of interest.
In this workflow, we build an indicator volume to highlight the areas of the reservoir with greatest potential. You can adapt this workflow to use any inputs!
After running an inversion and performing some analysis, we have some estimates of sand probability and porosity. In addition, we have a DHI volume. A valuable composite indicator would show areas that have a high probability of sand, porosity above 10%, with a positive DHI.
With a little formula know-how, we can do this using DUG Insight’s Volume Maths process.
Let’s create our indicator volume:
- Click on the Processes tab in the Control Panel.
- Add a New Process with the blue "+" button
- Search for Volume Maths .
Tip: Type the word Maths in the search to shorten the list
- Add the three volumes as inputs
- Type the formula:
if (v1>80 && v2 >10 && v3 == 1, 1, NaN)
What does this formula mean?
- Input volumes v1, v2 and v3 are the volumes we have chosen.
- We are using the && to combine the three tests; they must all be true.
- v1>80 : Is sand probability greater than 80%? AND
- v2>10: Is porosity greater than 10%? AND
- v3==1: Is the DHI value equal to 1?
- The if () statement reads as “if the statement is true then output this otherwise output this”
- If (statement, true, false)
- If all three conditions are true return a 1 otherwise return a NaN value
- NaN is a special value meaning “No value here”. It’s often called a null value.
- The output volume will have a value of 1 where all conditions are true and NaN elsewhere
Display the new indicator volume in any view, as part of a group for highlights or as geobodies in 3D View. Adapt the formula to fit your scenario and input data. This approach can be used for any number of properties and can be combined with other processes to provide deeper Insight!
Volume Maths is an extremely flexible and powerful tool. We’ve got more great ways to apply it in our other videos.
Enjoy Insight!