Evaluate Ogbon-1, End to End
Learning objectives
- Read the full interpretation chain on one well as four tracks plus a flag
- Trace shale volume, porosity, saturation, and permeability in order
- Flag net pay where the cutoffs all pass and sum the oil in place
- Read the entire interpretation at any single depth
One Well, the Whole Course
This is where everything comes together. The Ogbon-1 well, the same well the course has used chapter after chapter, is laid out as the complete interpretation: the gamma ray giving shale volume, the porosity, the Archie water saturation, the Timur permeability, and a flag that marks net pay where all of them pass their cutoffs.
The Chain in Order
Read left to right and it is the chain the whole course built, one track per step. The gamma ray separates sand from shale; the porosity says how much pore there is; the resistivity through Archie says how much of that pore holds oil; the permeability says whether it will flow. Where the shale is low, the porosity high, and the saturation low, the rock is net pay, and the green flag turns on.
Read It at a Depth
Scrub the cursor and the panel speaks for any foot of the well at once: a gamma-ray count becomes a shale volume, a density becomes a porosity, a resistivity becomes a saturation, all of it a single pay call. The running summary, the net pay, the average properties, and the oil in place, is the answer the next two sections turn into a decision. Every number here was earned by a chapter that came before.
References
- Asquith, G. and Krygowski, D. (2004). Basic Well Log Analysis, 2nd ed. AAPG.
- Crain, E. R. Crain's Petrophysical Handbook.