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PEF
2.6 .
MICA CONTENT
$0
SIDERITE CONTENT
volume % of whole rack
volume % of whole rock
° 10% 20% Q 10% 20%
Figure 9.30 The effect of siderite on the PEF log, High peaks on the log are caused by even small
quantities of siderite, which has a large, effective photoelectric absorption per unit volume, Uma
(Table 9.11). (From Humphreys and Lott, 1990).
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