Geoscience Reference
In-Depth Information
Table 11.1
Master relative chronology for drifts in the McMurdo Dry Valleys
Depth
(cm)
Thickness
salt pan
(cm)
Soil
sub-
group
f
No. of
sites
Max.
CDE
a
Vis.
Salts
Ice
cement
Salt
stage
b
Weathering
stage
c
HCP
index
e
Drift unit
Approx. age
Staining
Coherence
Ghosts
DPDI
d
Taylor Valley
(Bockheim et al.
2008
)
Alpine I
<3.7 Ky
3
0
11
0
0
16 (core)
0
1
0
GHt,
THt
Ross Sea
12.4-23.8 Ky
7
0
28
5
0
34
1.1
1.6
0
THt
pre-Ross
>12.4-23.8 Ky
3
0
23
0
0
25
1
1.7
0
THt
Alpine II
113-120 Ky
32
10
21
7
8
>40
1.5
2.1
0
THt-
TAo
Taylor II
113-120 Ky
14
3
18
3
6
>45
1.2
2.1
0
17
TAo-
THt
Taylor III
208-375 Ky
27
18
>46
21
9
>85
2
2.7
0
17
TAo
Taylor IVa
1.6-2.1 My
28
38
>48
33
15
>44
3.4
4.2
4
22
TAo,
SAo
Taylor IVb
2.7-3.5 My
18
33
>49
29
15
>46
2.8
4
4
21
TAo
Alpine III-IV
2.7-3.5 My
4
41
>47
41
14
>47
3.3
3.5
7
TAo
Wright Valley
(Bockheim and
McLeod
2006
)
Alpine I
<3.7 Ky
5
0 (0)
5 (4)
0 (0)
0 (0)
12 (8)
0 (0)
1 (0)
0
16
GHt
