HEAVY OIL IN
One way to test the techniques for ancient logs is to run the
math on a modern log suite and compare results to the same logs
after eliminating all the curves that would not have been available
in ancient times. In this well, we have conventional induction-electrical
and density-neutron logs in a heavy oil well. By assuming that
the induction resistivity is similar to a 64 inch normal and that
the only shale indicator is the SP, we can compare this "ancient"
log suite with the modern version in the identical rock/fluid
sequence using standard computer-aided log analysis.
IES and CNL FDC for heavy oil case history 1978
Conventional log analysis using GR, CNL, and
FDC. Pick water contact in GP sandstone. Is there a contact in
the Sparky sandstone? Compare your answer to resistivity log.
Same well computed with IES, SP, and PHIMAX
= 0.34. Compare to results in previous illustration.
the induction resistivity is focused better than a 64 inch normal,
this example shows that the PHIMAX method is quite suitable in
a shaly sand sequence.