Metallogenic Fingerprints of the Congo Shield with Predictions for Mineral Endowment Beneath the Congo Basin - Geology and Resource Potential of the Congo Basin - page 385

Fig. 19.4 Mineral diversity in
Central Africa, as shown by
plotting the natural log of the
spatial coefficient (ln r ij ; Y-axis)
of the five element groups (and
the total for the combined groups
[lower most plot]). Confidence
intervals are at 2 Standard

Error. Note how each geologic
domain has a unique combination
of elements that we term their
' Metallogenic Fingerprint ' . Note
that if the Confidence Interval
include 0, the fingerprint is
classed as random

We now transfer the expert-weight obtained from CA and
CAS across to the two inner areas CS and CB and we treat the
two inner regions CS and CB as one. Note that the inner areas
do not contain all of the geologic fields represented in the
outer areas (CA and CAS). Figure 19.9 compares the data
expressed in Figs. 19.4 , 19.5 , 19.6 at one scale in order to
compare each mineral group of all areas (viz. CA, CAS and
CB). The circles in the graphs of Fig. 19.9 indicate significant
fingerprints, (where significant

confidence intervals do not include 0 (e.g. In, in Figs. 19.4 ,
19.5 , 19.6 ). The significant fingerprints are summarised in
Table 19.3 and Fig. 19.9 .InTable 19.3 we include the
significant fingerprints obtained in the CS, but we exclude
them again to derive the

' '

shown in the last
column (right hand). Most of the CS patterns appear unstable
(large standard deviations), but the (significant) fingerprints in
the CS can be analyses further with, for example, greater
geologic knowledge of an

expert fingerprint

¼ fingerprints (bars) whose ' expert ' .