Not very old but not too young: thermochronological
constraints on the age of low-relief surfaces in the
western Himalaya and southeastern Tibet
Peter Zeitler (Lehigh University)
Copious thanks to Asif
Khan and David Shuster
Saturday, January 22, 2011
1
Low-relief landscapes abound
K
NP
D
LB
Clark et al. (2004),Tectonics 23:TC1006
van der Beek et al. (2009), Nature Geoscience 2: 364
Saturday, January 22, 2011
2
Low-relief landscapes
Saturday, January 22, 2011
3
Gamugah margin (Kohistan)
Saturday, January 22, 2011
4
SE Tibet
U-Th/He
data
zircon
apatite
Saturday, January 22, 2011
5
Saturday, January 22, 2011
6
Gamugah landscape,
Kohistan
LB
Indus R.
NP
Saturday, January 22, 2011
7
Gamugah
U-Th/He
apatite
Saturday, January 22, 2011
8
Saturday, January 22, 2011
9
Saturday, January 22, 2011
10
Saturday, January 22, 2011
11
Saturday, January 22, 2011
12
Saturday, January 22, 2011
13
Gamugah
U-Th/He
apatite
Saturday, January 22, 2011
14
Saturday, January 22, 2011
15
auses
c
s
s
e
roc
this ??
what p
Saturday, January 22, 2011
16
Summary
Some low-relief surfaces are neither ancient nor young...
... and aren’t steady state (buzz-saw missing a tooth?)
Significant rock and surface uplift at 7-10 Ma
... significant relief (> 2 km?) along middle Indus at ~8 Ma
Exhumation shuts down since 8 Ma – how?
Saturday, January 22, 2011
17