Sources and Effects of Fluids in Continental Retrograde Shear Zones: Insights from the Kuckaus Mylonite Zone, Namibia
Table 2
The overall trend of changes in element concentrations in selected shear zone rocks relative to their protoliths, across the KMZ, is loss of Fe2O3, MgO, and CaO and gain of SiO2, K2O, and Na2O.
Area
A
A
B
B
C
C
D
D
A(x)
D(x)
Sample
4
10
41
42
32
34
22
25
11
23
Rock type
TG
BG
BG
LG
TG
LG
BG
BG
BG
BG
SiO2
1.3
21.0
24.0
-41.8
19.9
-9.4
10.3
11.8
26.5
-6.8
TiO2
0.2
-51.0
-59.2
-39.7
-29.1
-5.3
-35.5
-35.2
-80.2
7.8
Al2O3
Fe2O3
-6.7
-59.4
-70.6
-42.9
-27.8
-18.3
-28.5
-17.5
-86.7
18.2
MnO
-34.5
-84.4
-92.3
-70.6
-29.2
5.8
-23.5
-22.2
-92.8
-1.4
MgO
-13.5
-88.3
-88.6
-28.7
-37.0
173.3
-21.0
-44.0
-93.5
31.9
CaO
-57.6
-80.0
-96.8
-54.7
-67.0
174.0
-19.3
-46.9
-96.1
10.3
Na2O
8.1
-7.9
16.5
788.8
30.6
8.7
0.2
9.3
-15.0
6.9
K2O
-11.8
119.6
74.6
-39.5
13.3
-16.6
0.1
37.1
153.6
-35.5
P2O5
-56.9
-42.4
-63.4
-82.2
-72.2
-17.2
-34.7
-27.7
-82.4
11.2
NiO
-46.3
-7.1
-21.0
-35.3
-41.3
-6.0
-30.6
6.7
343.5
-19.4
TG=Tsirub Gneiss; BG=biotite gneiss; LG=leucogranite; (x)=enriched in K-feldspar/epidote/chlorite. Loss=italics. Gain=bold.
