RHOC
Schlumbergerlbm/gal[US]Bulk Density (Coal-Corrected)
A bulk-density variant processed for coal-like, low-density formations — the density curve with corrections suited to the very low densities and high hydrogen content of coal seams, where standard RHOB processing can misread.
- Property
- Bulk Density
- Density
- Quantity
- mass per volume
- lbm/gal[US] · 0.01 grain/ft³ · µg/cm³ · grain/gal[US] · lbm/gal[UK] · 0.001 lbm/gal[UK] · 0.001 lbm/bbl · kg/dm³ · g/gal[UK] · g/m³ · mg/dm³ · t/m³ · mg/gal[US] · g/L · lbm/in³ · mg/m³ · 10 Mg/m³ · mg/L · lbm/ft³ · kg/L · lbm/bbl · 0.001 lbm/gal[US] · Mg/m³ · 0.1 lbm/bbl · g/cm³ · g/gal[US] · grain/ft³ · g/dm³ · kg/m³
- Typical range
- ~-0.1–0.3 g/cm³
- g/cm³, low in coal (~1.2–1.8)
Logging tool
No logging tool is associated with this curve.
Service company
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View Schlumberger mnemonics →What is the RHOC curve?
How it's measured
The gamma-gamma density measurement with processing tuned for coal-like intervals, where extreme low density and washout-prone seams challenge the standard spine-and-ribs correction.
How it's used
Coal identification and net-coal evaluation, ash-content estimation, and porosity where coal or very low-density lithologies would bias the standard density.
Common gotchas
Coal seams wash out badly, so even the corrected density can be unreliable in rugose intervals — check the caliper and DRHO. Outside coal it offers no advantage over standard RHOB.
In LAS files
Recorded as RHOC in g/cm³, a specialized companion to RHOB. Expect very low values across coal.
Also seen with RHOC in real logs
Curves that appear alongside RHOC in the same wells across the public corpus.