2. Gamma log has three types-
1.True gamma log /Normal gamma log
2.Spectral gamma log
3.Gamma-Gamma log /Scattered gamma log
3. PRINCIPLE
The formation density tools are induced
radition tools
They bombard the formation with radition
and measure how much radition returns to a
sensor
5. Tool consist of-
A radioactive source: Caesium-137 and Cobalt-60
A short range detector: Placed 7 inches from the
source.
A long range detector: Placed 16 inches from the
sources.
PROCESS OF MEASURING
6. DETERMINATION OF POROSITY
The porosity of a
formation can be obtain
from the bulk density if
the mean density of the
rock matrix and that of
the fluids it contains are
known.
fma
bma
9. USES OF THE FORMATION DENSITY
LOG
Determine total porosity of the formation.
Recognition of gas bearing zone.
Identification of minerals(particularly
evaporites).
The combination of formation density log
data with neutron log data gives one of the
best ways of identifying lithologies in a
borehole.
10. References
Ellis, D. V., & Singer, J. M. (2007). Well logging for earth
scientists(Vol. 692). Dordrecht: Springer.
Darling, T. (2005). Well logging and formation evaluation.
Elsevier.
Johnson, D. E., & Pile, K. E. (2002). Well logging in
nontechnical language. PennWell Books.