1. Step 1: Lithology Using the Gamma Ray log, define a shale base line
ILD (deep)
Using the Gamma Ray log, define a shale base line
Deflections far to the left are sands
Intermediate deflections to the left are silts
Gamma Ray
Caliper
Sandstone
Siltstone
Shale
MSFL
NPHI
SFL
RHOB)
SLIDE 11
First we can interpret lithology based on the gamma log
Red dashed line = shale baseline
Depth range subdivided into 3 litho-types
High gamma, near baseline = shale (green)
Low gamma = sandstone (yellow)
Intermediate = silt (brown)
Courtesy of ExxonMobil
L 4 - Well Log Data