Question 7 from past paper.
Here you are asked to determine lithology at 4 different depths using Neutron-density and M&N plots.
Take first given depth, 11410 ft
Write these values on the plot
DENS – 2.6 g/cc
CNL – 4 % 2.55
2.65
9
3
0.1
6
Limestone (limestone is a carbonate)
In the same way you work with other depths
CNL – 4 % DENS – 2.6 g/cc 10
60
50
SONI – 57 us/ft
From M&N plots
At the same depth of 11410ft
DENS – 2.6 g/cc
CNL – 4 % = 0.04
SONI – 57 us/ft
From M&N plot it is also limestone
According to resistivity log, deep resistivity reading is slightly higher,suggesting fresh formation water