Kaolinite and Chlorite as Tracers of Modern and Late Quaternary Deep Water Circulation
299
Isotope Stages
1 2
3
4
5
6
7
8
1.1
2.0
0
0.9
2.5
.~
EO
0
a:
3.0
n..
:c 0.7
t
()
C
3.5
0
Cll
~
a)
0.5
:0
4 .0
0.3
4.5
25
*
20
D Chi
ro
(jj
15
c
~
>D Kao
Cll
10
(3
5
0.20
(u
0.15
~
D Chi
N
E 0.10
u
Cl
g
D Kao
a: 0.05
«
0.00
0
50
100
150
200
250
300
Age (ka)
Fig. 7. Temporal variations of the kaolinite/chlorite-ratio (solid line, upper graph), kaolinite and chlorite percentages (central graph), and kaolinite and chlorite accumulation rates (lower graph) documented in sediment core
PS2495-3 from the Mid-Atlantic Ridge . The applied age model was deduced from the benthic foraminiferal 8 1 ' 0
record of Cibicidoides wuellerstorfi (grayish colored curve, upper graph) (Mackensen, unpublished).
kaolinite source in glacial times, as is today, may
be the Vema Channel region where a greater supply of kaolinite-bearing sediment from the adjacent
continent to the western flank of the Vema Channel (Sao Paulo Plateau) occurred (Masse et al.
1996). These stronger kaolinite fluxes during gla-