CALCULATING
Shale Volume FRM RESISTIVITY LOG
In bitumen bearing oil sands or heavy oil, you can add the
deep resistivity
method for calculating shale volume. The purpose is to eliminate small Vsh
anomalies caused by feldspar or uranium salts in the reservoir. The method works
best with Phasor or Array Induction and High Res Laterologs, but may also be
helpful in SAGD projects with olde logs.
1:
Vshr = (log(RESD) - log(RMAX)) / (log(RSH) - log(RMAX))
Where:
RESD = deep resistivity log reading (ohm-m)
RMAX = deep resistivity reading in clean oil sand (ohm-m)
RSH = deep resistivity log reading in shale (ohm-m)
Vshr = shale volume from deep resistivity (fractional)
DOES NOT work
in water zones so combine this methhod with any other feasible model to handle
the water zones.
Bitumen sand example using Vsh calculated from minimum of Vshr and
Vshgr. Final Fsh is light gray in lithology track at far right.
|