Ratio of effective formation thickness to the total thickness of formation unit:
| {\rm NTG} = \frac{h_{\rm eff}}{h_{\rm total}} |
This value is usually used for fast calculation of effective formation thickness from total thickness of formation unit during the flow rate predictions from a given well.
The NTG Thickness is closely related to NTG Volume with both concepts are matching when calculated along well trajectory.
See also
Petroleum Industry / Upstream / Subsurface E&P Disciplines / Petroleum Geology