CILD
SchlumbergerS/mDeep Induction Conductivity
The calibrated deep-induction conductivity — the corrected reciprocal of deep resistivity (ILD). It reads high in conductive, saline, water-bearing rock and low in resistive hydrocarbon or tight zones.
- Property
- Deep Induction Conductivity
- Deep Conductivity
- Quantity
- electric conductivity
- S/m · mS/m · mS/cm · kS/m
- Typical range
- ~15.6–663.4 mmho/m
- mmho/m (mS/m), conductivity
Logging tool
No logging tool is associated with this curve.
Service company
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How it's measured
The deep induction array's conductivity after skin-effect and environmental calibration — the corrected form of the raw RILD and the direct inverse of ILD resistivity.
How it's used
Deep formation conductivity for saturation and hydrocarbon identification; some workflows prefer conductivity (which induction measures directly) over its resistivity reciprocal, especially at low resistivity.
Common gotchas
Conductivity emphasizes low-resistivity (water) zones and compresses high-resistivity contrast — the opposite tradeoff of resistivity. The usual induction limits apply in salt muds and very resistive rock.
In LAS files
Recorded as CILD in mmho/m (or mS/m) — the calibrated partner of RILD and the inverse of ILD.
Also seen with CILD in real logs
Curves that appear alongside CILD in the same wells across the public corpus.