Part 2 – Manual Fault-Plane Interpretation with OpendTect
In last week's post, we illustrated why cleaning up your seismic data and visualizing faults are crucial first steps in any fault-interpretation workflow.
Now, in Part 2, we move into the hands-on stage: manually picking fault sticks and constructing a fault plane in OpendTect to build a geologically sound structural framework. This can be done in two ways: either on a plane-by-plane basis, or by picking and grouping afterwards.
In the slides attached you’ll see an example of the first workflow. You need to click on the picture attached to see the animation.
The workflow we followed:
🔹 Improve the legacy seismic data with a Dip-Steered Median Filter (DSM)
Compute Thinned Fault Likelihood (TFL)
🔹 On-the-fly compute the RMS of TFL attribute and display as overlay on DSM
🔹 Manually pick fault sticks belonging to one plane on one inline guided by RMS of TFL
🔹 Move the inline 10 steps (use keyboard shortcuts Z and X)
🔹 Pick sticks that belong to the same fault plane on the next inline
Repeat 5 and 6 until the entire plane is picked and Save.
Key take-aways
🔹 Manual construction of a single fault-plane is performed by picking fault sticks either on inlines and crosslines, or on time-slices
🔹 The workflow is facilitated by pre-processing the seismic data and using overlays of a fault attribute such as RMS of TFL
Stay tuned for Part 3, where we’ll examine manual fault interpretation by first picking sticks followed by grouping sticks into planes. The series will be finalized in Part 4, where we discuss Automated Fault Plane extraction.
I’d love to hear how you integrate manual vs automatic workflows in your projects—share your experiences, challenges or favourite tools below!