figure pages in: sedimentology, petrography, and tectonic
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This pdf file contains all figure pages in the dissertation:
Fig
ure
1.1
Him
alay
as-T
ibet
an P
late
au T
opog
raph
y (f
rom
http
://w
ww
.geo
.cor
nell.
edu)
.T
his
imag
e is
a f
alse
-col
or, s
hade
d re
lief
imag
e w
ith il
lum
inat
ion
from
the
nort
hwes
t. T
he s
hado
win
g gi
ves
an in
dica
tion
of lo
cal r
elie
f w
hile
col
or in
dica
tes
elev
atio
n as
fol
low
s: m
agen
ta=
sea-
leve
l; bl
ue=
1000
m; c
yan=
2000
m; g
reen
=30
00m
; ye
llow
=40
00m
; red
=50
00m
; whi
te=
6000
m a
nd a
bove
.
2
Kat
awaz
Koh
ista
nLa
dakh
Zan
skar
Lha
sa B
lock
BN
S
Indi
a
IYZ
S
Gam
ba
Tin
gri
Mal
la J
ohar
Haz
ara
30N
25N
30N
25N
70E
80E
90E
70E
80E
90E
HF
Indi
an P
late
Les
ser
Him
alay
a
Hig
h H
imal
aya
Cry
stal
lines
Koh
ista
n-L
adak
h A
rc C
ompl
ex
Tet
hyan
Him
alay
a
Lha
sa B
lock
Indo
-B
urm
an R
ange
MC
T
STD
S
Inne
r-bu
rman
Bas
in
Qia
ngta
ng B
lock
Figu
re 1
.2 R
egio
nal g
eolo
gica
l m
ap o
f T
ethy
an H
imal
aya
(mod
ifie
d af
ter
Row
ley,
199
6)B
NS:
Ban
ggon
g-N
ujia
ng S
utur
e IY
ZS:
Indu
s-Y
arlu
ng-Z
angb
o-Su
ture
, MC
T:M
ain-
Cen
tral
-Thr
ust,
STD
S:So
uthe
rn-T
ibet
-Det
achm
ent-
Syst
em
Xig
aze
Lha
sa
Gya
ngze
4
India
Shelf Rise Trench
Asia
Gangdese Arc
Ophiolites
TuffFlysch
(1)
(2)
(3)
Figure 1.3 Schematic cross-sections of the India-Asia convergence up to the initiation of collision (modified after Rowley and Kidd, 1981). (1) Cretaceous; (2) Paleocene; (3) Eocene.
5
Qt
F L
Con
tinen
tal B
lock
Pro
vena
nce
Magmatic Arc Provenance
Recycled OrogenProvenance
Qm
F Lt
Con
tinen
tal B
lock
Pro
vena
nce
Magmatic Arc Provenance
Recycled O
rogen
Provenance
Mixed
Figure 1.4 Detrital mode distribution in three major tectonic settings. After Dickinson et al. (1983).Qt: monocrystalline quartz+polycrystalline quartz; Qm:monocrystalline quartz; F: feldspar, L:rock fragments; Lt: rock fragments+polycrystalline quartz.
8
Gy rong-Kangmar Thrust
Lhasa Block
Indus-Yarlung Tsangpo-Suture
High Himalaya
NepalBhutan
Yadong
KangmarTianba
Gyangtse
Xigaze
Gamba
Tingri
Lhaze
100 km
India
Tethyan Himalaya - N
Tethyan Himalaya - S
TibetIYZS
Figure 2.1 Simplified geologic map of Tingri-Gyangtse area, southern Tibet (modified after Willems et al., 1996). The inset map shows this region located in the Himalaya system.
17
Gamba E1-2
E1-2
K2
K2
K2
K2
K1
K1
K1
K1
K1
Q
Q
Q
J3 J3
J3
J3
J3
J3
J3
J3
J1-2
J1-2
T
Tatsang
10 km
Figure 2.2 Simplified geologic map of the Gamba region (modified after geologic map (1:1,500,000) in Xizang BGMR, 1992).
18
Figu
re 2
.3 G
eolo
gic
map
of
the
Zhe
pure
Sha
n M
ount
ain
(bas
ed o
n fi
eld
obse
rvat
ions
and
imag
e in
terp
reta
tion
(Kid
d)).
Geo
grap
hic
coor
dina
tes
in d
egre
es, m
inut
es.
27
86 4
686
50
86 4
2
28 4
2
28 4
4
28 4
6
28 4
0
28 3
8
28 3
6
28 3
4
86 3
886
54
86 5
887
02
Peng
qu R
iver
Nep
al-L
hasa
Roa
d
To
Old
Tin
gri
Shek
ar D
zong
Shen
keza
Y
ouxi
a
Gon
gza
Sect
ion
Zhe
pure
Sha
n R
ange
Shen
keza
FM
You
xia
FM.
Zhe
pure
Sha
n FM
.
Jidu
la F
M
Pre-
Jidu
la F
M
Faul
t
Kat
awaz
Koh
ista
nL
adak
h
Zan
skar
Lha
sa B
lock
BN
S
Indi
a
IYZ
S
Gam
ba
Tin
gri
Mal
la J
ohar
Haz
ara
30N
25N
30N
25N
70E
80E
90E
70E
80E
90E
Raj
mah
al
Indi
an P
late
Les
ser
Him
alay
as
Hig
h H
imal
ayas
Cry
stal
line
Koh
ista
n-L
adak
n A
rc C
ompl
ex
Tet
hyan
Him
alay
as
Lha
sa B
lock
Indo
-B
urm
an R
ange
MC
T
STD
S
Inne
r-bu
rman
Bas
in
Qia
ngta
ng B
lock
Xig
aze
Lha
sa
Figu
re 2
.
Figu
re 3
.1 R
egio
nal g
eolo
gica
l m
ap o
f T
ethy
an H
imal
aya
(aft
er R
owle
y, 1
996)
. BN
S: B
angg
ong-
Nuj
iang
Sut
ure
IYZ
S:In
dus-
Yar
lung
-Zan
gbo-
Sutu
re, M
CT
:Mai
n-C
entr
al-T
hrus
t, ST
DS:
Sout
hern
-Tib
et-D
etac
hmen
t-Sy
stem
.
45
Nepal im BhutanYadong
100 km
Tethyan Himalaya - S
Tethyan Himalaya - N
High Himalaya
Lhasa Block
Xigaze
Kangmar Tianba
Gamba
Tingri
Lhaze Gyangtse
Indus-Yarlung-Zangbo-Suture
Gyirong-Kangmar Thrust
Figure 3.
Figure 3.2 Simplified tectonic map of the study area (after Willems et al, 1996)
46
5 km
89.80 89.90
Gyangtse-Lhasa roadJiabula
Grey shales, quartzites and marls
Black cherts and shales
Tianba Flysch and overlying shales
Melange (area of pink limestone blocks shown)
Nieru V
alley
Tianba28.70
28.80Fault
Fault
Figure 3.3 Sketch geologic map at Tianba showing three measured sections 1-3.Note: Rivers are traced from the 1:100,000 topographic map
48
3
1 2
Figu
re 3
.4. T
ianb
a cr
oss-
sect
ion
(sec
tion
2, s
ee f
igur
e 3.
3 fo
r lo
catio
n) H
oriz
onta
l sca
le=
vert
ical
sca
leSe
e Fi
gure
3.1
1 fo
r ex
plan
atio
n of
lith
olog
ic u
nits
and
orn
amen
ts.
4300
m
4400
m
4500
m
4600
m
N
7
6
5
43
2
1
8
49
Figu
re 3
.5 V
iew
to n
orth
of
Tia
nba
sect
ion.
Dar
k gr
ey s
hale
s an
d ch
erts
are
of
earl
y C
reta
ceou
s se
dim
ents
in th
e ri
ver
valle
y an
d th
e lo
wer
slo
pes
of th
e hi
lls b
eyon
d; ta
n-or
ange
ban
d is
the
Tia
nba
Flys
ch; p
ink-
purp
le r
ocks
abo
ve th
is a
re f
ault-
juxt
apos
ed la
te C
reta
ceou
s lim
esto
nes
and
shal
es.
[The
aut
hor,
Bin
Zhu
, in
this
pic
ture
]
Mea
sure
d se
ctio
n2T
ianb
a Fl
ysch
50
(1)
(2)
Figure 3.6 Sedimentary structures in the Tianba Flysch(1) Ripple marks; (2) Sole marks.
51
Figure 3.7 Well-bedded turbidite sandstones with shale interbeds in the center part of the Tianba Flysch. View to east, section youngs to north (left).
52
Figu
re 3
.8 T
op o
f th
e T
ianb
a Fl
ysch
, nor
th o
f T
ianb
a vi
llage
. The
upp
erm
ost t
hick
-bed
ded
sand
ston
e of
the
Tia
nba
Flys
ch is
on
the
righ
t. V
iew
to E
NE
, sec
tion
youn
gs to
nor
th (
left
).T
he d
ark
grey
sh
ales
con
form
ably
ove
rlie
the
Tia
nba
flys
ch.
54
Figu
re 3
.9 S
ider
itic
sand
ston
e be
d sh
owin
g gr
aded
-bed
ding
. Abu
ndan
t Cr-
rich
spi
nels
are
fo
und
in th
ese
sand
ston
es.
55
Figu
re 3
.10
Out
size
d (u
p to
1 m
acr
oss)
cal
care
ous
nodu
les
in th
e gr
eeni
sh-g
rey
shal
es,
nort
h of
Tia
nba
villa
ge. V
iew
to N
E. O
ne s
mal
l nod
ule
(10
cm a
cros
s) y
ield
ed a
n am
mon
ite. [
Dr.
B. Z
hang
in th
is p
ictu
re]
56
7. Melange .
0
50
100
150
200
250
300
350
400m
-50
-100
-150
m
limestone
sandstone
coarse sandstone
siltstone
shale
mudstone
chert
melange
marlstone
Figure 3.11 Measured Section (2), north of Tianba village. See Figure 3.3 for location.
TB-5
TB-6
TB-7
TB-12
TB-13
TB-14
B
A
TB-33
Tia
nba
Flys
ch
sandstone with spinel sandstone without detected spinel
TB-11
DB-1
D4
Fault
8. Purple, medium-bedded and blocky siliceous limestone with lenses of red shale (late Cretaceous)
5. Grey-green burrowed shale, heavily pencilled with 3 lenticular siderite sandstones beds
6. Dark grey and green shales with large carbonate nodules in the upper part.Ammonite (A) and Belemnite (B)
4. Grey to green, medium- to thick-bedded siltstone and sandstone, interbedded with shale (one 30 cm black limestone).
3. Yellowish-green micaceous siltstones
2. Black chert, siliceous mudstones and shales, and minor marlstones.
1. Black shales and minor mudstones and cherts.
Minor Fault
57
?
100
200
300
400
-100
-200
-300
-400
0
500m
Tia
nba
Fly
sch
Fault Fault
Fault
Section 3 Section 1 Section 2
Figure 3.12 Measured stratigraphic sections at Tianba. Section locations are shown in Figure 3.3 See Figure 3.11 for explanation of the lithologic ornaments.
59
300
um
Figu
re 3
.13
Phot
omic
rogr
aph
(cro
ssed
pol
ars)
of
quar
tz-r
ich
sand
ston
e in
the
basa
l par
t of
wes
tern
se
ctio
n (s
ectio
n 3
in F
igur
e 3.
3). Q
uart
z gr
ains
are
mos
tly m
onoc
ryst
allin
e,an
d th
e ro
ck is
wel
l-so
rted
.
60
30 u
m
Figu
re 3
.14
Phot
omic
rogr
aph
(cro
ssed
pol
ars)
of
a m
etam
orph
ic r
ock
frag
men
t in
the
quar
tz-r
ich
sand
ston
es in
the
basa
l par
t of
wes
tern
sec
tion
(sec
tion
3, s
ee f
igur
e 3.
3 fo
r lo
catio
n.
61
Qt
LF
Chulung La Arenite (Garzanti, et al., 1987)
Giumal sandstone (Garzanti, et al., 1987)
Greywackes
Quartz arenites
Recycledorogen
Qm
LtF
Recycled
orogen
Figure 3.15 Detrital mode plot of sandstones in the Tianba sections. Tectonic fields from Dickinson and Suczek, 1979. Giumal sandstones and Chulung La Arenite from Zanskar are shown for reference on the QtFL plot.
62
300
um
Figu
re 3
.16
Phot
omic
rogr
aph
(pla
ne p
olar
s) o
f gr
eyw
acke
s in
the
Tia
nba
mea
sure
d se
ctio
n.N
ote
angu
lar
quar
tz g
rain
s ar
e po
orly
-sor
ted,
and
ther
e ar
e so
me
feld
spar
gra
ins
(dus
ty/d
irty
lo
okin
g co
mpa
red
with
cle
arer
qua
rtz
grai
ns).
63
100
um
Figu
re 3
.17
Phot
omic
rogr
aph
(cro
ssed
pol
ars)
of
feld
spar
(pe
rthi
te)
in th
e gr
eyw
acke
s of
the
Tia
nba
sect
ion
2 (s
ee f
igur
e 3.
3 fo
r lo
catio
n).
65
30 u
m
Figu
re 3
. 18
Phot
omic
rogr
aph
of a
vol
cani
c ro
ck f
ragm
ent c
ompo
sed
of p
lagi
ocla
se
phen
ocry
sts
with
in f
ine-
grai
ned
grou
nd m
ass.
Thi
s in
dica
tes
that
ther
e w
as a
sig
nifi
cant
vo
lcan
ic s
ourc
e fo
r th
e T
ianb
a Fl
ysch
.
66
30 u
m
Figu
re 3
.19
Phot
omic
rogr
aph
(cro
ssed
pol
ars)
of
a ro
ck f
ragm
ent w
ith tr
achy
tic te
xtur
e in
T
B6
sam
ple
in th
e T
ianb
a se
ctio
n 2
(see
fig
ure
3.3
for
sect
ion
loca
tion)
.
67
Figu
re 3
.20
His
togr
am s
how
ing
the
diff
eren
t det
rita
l mod
es b
etw
een
quar
tzite
and
gre
ywac
kes
in th
e T
ianb
a se
ctio
ns. T
hese
san
dsto
nes
have
sim
ilar
quar
tz c
onte
nts,
whi
le th
ere
are
mor
e m
atri
x, f
elds
par,
vol
cani
c lit
hics
and
le
ss m
etam
orph
ic li
thic
s in
the
grey
wac
kes
com
pare
d to
the
quar
tzite
s. M
onoq
uart
z: m
onoc
ryst
allin
e qu
artz
; Pol
yqua
rtz:
pol
ycry
stal
line
quar
tz; P
lag:
pla
gioc
lase
; K-s
par:
K-f
elds
par;
V
-lith
ic: v
olca
nic
lithi
cs; M
-lith
ic: m
etam
orph
ic li
thic
s; S
-lith
ic: s
edim
enta
ry li
thic
s; o
paqu
e: o
paqu
e m
iner
als.
68
Gre
ywac
kes
Qua
rtz
aren
ites
Figu
re 3
.21
Che
mic
al c
ompo
sitio
ns o
f de
trita
l Cr-
rich
spi
nels
usi
ng p
airs
plo
t fro
m S
-plu
s
TiO
2
Al2
O3
Cr2
O3
MnO
MgO
NiO
FeO
Fe2O
3
74
Figure 3.22 Backscattered electron images of melt inclusions in the
detrital spinels from Tianba Flysch.
a.
b.
c.
76
Mg/(Mg+Fe2+)
0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9
V2O
5
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
Mg/(Mg+Fe2+)
0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9
MnO
0.15
0.20
0.25
0.30
0.35
0.40
0.45
Tianba Flysch spinels Hawaii Disko
Mg/(Mg+Fe2+)
0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 N
iO
0.00
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.40
Mg/(Mg+Fe2+)
0.2 0.3 0.4 0.5 0.6 0.7
ZnO
0.05
0.10
0.15
0.20
0.25
0.30
Figure 3.23 Covariation of minor elements with Mg/(Mg+Fe2+) in spinel
(For comparision, data from Hawaii and Disko are also shown):
a. MnO vs. Mg#; b. NiO vs. Mg#; c. ZnO vs. Mg#; d. V2O5 vs. Mg#.
a b
c d
78
0.2
BoninitesIsland-arc basalts
Intra-plate basalts
Back arc basin
MORB
TiO
2 w
t%
Flysch
DiskoHawaii
Figure 3.24 Major element contents of spinels and tectonic setting discriminant plot:a. Cr/(Cr+Al) vs. Mg/(Mg+Fe2+) after Barnes and Roeder, 2001; b. TiO2 vs. Cr/(Cr+Al) after Arai, 1992.
Mg/(Mg+Fe2+)
Isopleths of olivine Fo (dashed lines) from Kamenetsky et al, 2001
OIB
Arc
Boninites
Flysch
DiskoHawaii
Fo80
-81
Fo85
-86
Fo87
-88
Fo89
-90
MORB
Hawaii
a
b
Cr/(Al+Cr)
Cr/
(Al+
Cr)
80
0.01
0.1
1.00
10.0
10 20 30 40
CFB OIB
MORB
ARCWest Greenland
Al2O3%
FlyschDiskoHawaii
Fe3+/(Al+Cr+Fe3+)
Flysch
DiskoHawaii
Intra-plate basalt
MORBARC
TiO
2 w
t%T
iO2 w
t%
c
d
Figure 3.24(continued) Major element contents of spinels and tectonic setting discriminant plot:c. TiO2 vs. Fe3+/(Al+Cr+Fe3+) after Arai, 1992; d. TiO2 vs. Al2O3 after Kamenetsky et al, 2001.
81
100
Zanskar
Figure 3.25 Comparison of lithostratigraphy between Tianba, Zanskar (after Garzanti, 1993), Thakkhola (Garzanti, 1999) and Wolong (Jadoul, et al. 1998).
Chikkim Fm.
Pingdon La Fm.
Takh Fm.
Spiti Fm.
Thakkhola Wolong
Spiti Fm.
Dangardzong Fm.
Kagbeni Fm.
Dzong Fm.Wolong Fm.
Tianba Flysch
0
200
300 m
-100
-200
-300
-400
Volcaniclastic sandstones
Quartz arenites
Shales and cherts
Limestones
Shales
Jiabula Fm.
Tianba
Fault
85
(a)
(b)
94
Gy
rong
-Kan
gmar
Thr
ust
Lha
sa B
lock
Indu
s-Y
arlu
ng T
sang
po-S
utur
e
Hig
h H
imal
aya
Nep
alB
huta
nY
adon
g
Kan
gmar
Tia
nba
Gya
ngts
e
Xig
aze
Gam
ba
Tin
gri
Lha
ze
100
km
Ind
ia
Tet
hyan
Him
alay
a -
N
Tet
hyan
Him
alay
a -
S
Tib
etIY
ZS
Figu
re 4
.2 S
impl
ifie
d te
cton
ic m
ap o
f th
e st
udy
area
(aft
er W
illem
s et
al,
1996
).T
he in
set m
ap s
how
s th
e T
ingr
i-G
yang
tse
area
in th
e H
imal
ayan
sys
tem
.
95
a. b.
c. d.
98
Figure 4.4 Major element contents of spinels and tectonic setting discriminant plots:a.TiO2 vs. Al2O3 after Kamenetsky et al[14]. Studies of Cr-rich spinel compositions from different tectonic settings show that TiO2 and Al2O3 contents of spinel form a linear trend for those from Continental Flood Basalts (CFB), OIB, DI (Disko Island, W. Greenland), and MORB. Our data mostly plot in the middle of this trend, mainly in the OIB field.b.Cr-Al-Fe3+ ternary plot. 95% of the detrital spinels plot in the 90th percentile contours of OIB field. Different fields are from Barnes and Roeder[33]: 1-MORB; 2-OIB; 3-Island Arc; 4-Boninites.
b.
0.01
0.1
1.00
10.0
10 20 30 40
TiO
2 w
t%
Al2O3 wt%
CFB
Arc
MORB
OIB
Al1
2
3
4
a
DI
101
Figure 4.5 Elemental maps of a melt inclusion quenched from 1250C, showing the homogenised melt inclusion.a. Backscatter image of the melt inclusion; b. X-ray image of Al distribution;c. X-ray image of Cr distribution; d. X-ray image of Mg distribution;e. X-ray image of Fe distribution; f. X-ray image of Ti distribution.
a. b.
c. d.
e. f.
102
Figure 4.6 Major-element compositions of melt inclusions in the detrital spinels from Tianba Flysch. Note K2O, TiO2, Al2O3, P2O5, and Na2O are increasing with dereasing MgO, showing relative enrichment of incompatible elements consistent with the crystallization of olivine and spinel.
105
BasaltPicro-basalt
TephriteBasanite
Phono-tephrite
Trachy-basalt
BasalticAndesite
Andesite
Dacite
Basaltictrachy-andesite
Trachy-andesite
Trachyte
Tephri-phonolite
RhyoliteFoidite
Alkalic
Tholeiitic
Figure 4.7 Total alkalis vs silica plot after Le Bas et al. [34]. The Macdonald-Katsura line that divides the tholeiitic series from the alkalic series is from Macdonald and Katsura[35]. In our glass data, there are 13 analyses with Na2O content >1 wt%, and only one plots in the tholeiitic area, hence the parental magma of these melt inclusions must be alkali basalt.
107
Figure 4.8 Positive correlation between Al2O3 and TiO2 contents in melt inclusions and hosted spinels (the best fit lines and fields are from Kamenetsky et al., 2000). Continuous line in a. is a power law best fit through published data; Continuous and dashed lines in b. are best fit through the high-Al (Al2O3 in melt >14 wt%) and low Al (Al2O3 in melt<14 wt%) data, respectively. Our data are either close to, or aligned with their best fit lines. The relatively narrow range of our data and proximity to the OIB point suggest a single tectonic provenance for these detrital spinels.
Spinel Al2O3 wt%
Mel
t Al 2
O3 w
t%
spinel TiO2 wt%
mel
t TiO
2 wt%
OIB
ARC
MORB
ARC
OIB
MORB
a
b
109
Figure 4.9 TiO2-MnO-P2O5 plot (after Mullen, 1983). CAB: Calc-Alkaline basalts; IAT: Island Arc Tholeiites; OIA: Ocean Island Alkali basalt or Seamount Alkali Basalt; OIT: Ocean Island Tholeiites. 13 of data (Na2O>1 wt%) plot in, or very close to, the OIA field. Therefore the melt of the spinel melt inclusions was most like oceanic island basalt. R represents the field of Rajmahal Traps (data from Storey et al., 1992).
110
CAB
IAT
MORB
OIT
OIA
MnO*10 P2O5*10
TiO2
R
Arc
MO
RB
Hot
spot
Figu
re 4
.10
Dis
crim
inan
t fun
ctio
n pl
ot o
f ba
salt
from
thre
e te
cton
ic s
ettin
gs.
The
com
posi
tions
of
basa
lt (S
iO2:
40-
55 w
t%)
from
Izu
Isl
and
Arc
(50
), A
ndea
n A
rc(5
0), M
aria
nia
Arc
(50
), H
onsh
u A
rc(5
0), M
OR
B(2
00),
H
awai
i(50
), I
cela
nd(5
0), K
ergu
elen
Isl
and
(50)
, and
Can
ary
Isla
nd (
50)
are
used
to d
evel
op th
is p
lot u
sing
line
ar
disc
rim
inan
t fun
ctio
n(ld
a) in
Spl
us [
29].
11
of 1
3 m
elt i
nclu
sion
s in
Tia
nba
Flys
ch p
lot i
n H
otsp
ot b
asal
t fie
ld, a
nd
no p
oint
s pl
ot in
arc
fie
ld. R
ajm
ahal
dat
a fr
om K
ent e
t al.,
1997
; Sto
rey
et a
l., 1
992.
D1=
2.02
*log
(SiO
2/T
iO2)
-2.1
5*lo
g(A
l 2O3/
TiO
2)-3
.14*
log(
FeO
/TiO
2)+
0.82
*log
(CaO
/TiO
2)+
0.41
*log
(MgO
/TiO
2)-1
.07*
log(
K2O
/TiO
2)-0
.37*
log(
Na 2
O/T
iO2)
+0.
53*l
og(P
2O5/
TiO
2)D
2=1.
69*l
og(S
iO2/
TiO
2)-2
.88*
log(
Al 2O
3/T
iO2)
-0.0
9*lo
g(Fe
O/T
iO2)
+0.
85*l
og(C
aO/T
iO2)
-0.4
9*lo
g(M
gO/T
iO2)
-1.1
5*lo
g(K
2O/T
iO2)
+3.
48*l
og(N
a 2O
/TiO
2)-0
.17*
log(
P 2O
5/T
iO2)
Raj
mah
al
111
Figure 4.11 Reconstruction map at about 117 Ma (modified after Besse and Courtillot, 1988). MAD, Madagascar block; S.TIB, southern Tibet; RT, Rajmahal Traps; TF, Tianba Flysch. The red line is the major subduction zone.
Eurasia
ArabAfrica
Australia
S.TIB
Neo-Tethys
India TF
RT
Antarctica
115
K2O
Al2O3
CaO*+Na2ONatural Waters
Plagioclase K-Feldspar
Muscovite
Illite
Kaolinite,Gibbsite, Chlorite
Pred
icte
d w
eath
erin
g tre
nd
TB5
TB6TB7
TB1
TB13
TB14
TB8
TB4, TB10, TB11
Figure 5.1 CIA ternary plot of the Tianba Flysch. Modified after Bock et al. (1998). The enrichment in Al2O3 and depletion of CaO+Na2O+K2O reflect the degree of chemical weathering to which the materials have been subjected. Four analyses (TB1, TB7, TB13, TB14) defined a linear trend encompassed in the predicted weathering trend for the average upper crustal composition. Four shales do not follow the predicted weathering trend, indicating processes in addition to the weathering have affected these sediments. TB6 and TB5 plot close to the Al2O3-CaO+Na2O join, which may indicate a signficant volcanic input.
Shales
Sandstones
Siltstone
Upper crust
120
Figure 5.2 SiO2-Al2O3 plot of the Tianba Flysch. TB5 (based on CaO and LOI-free recalculation) is not in the linear trend formed by the rest of analyses in Tianba Flysch.PAAS from Taylor and McLennan (1985), average basalt composition from Condie (1993).
122
Figure 5.3 MgO-FeOt plot of the Tianba Flysch.TB14 (siltstone) has high Fe content falling off the Fe-Mg trend of the other analyses. PAAS from Taylor and McLennan (1985), basalt from Condie (1993).
124
125
Figure 5.4 Al2O3-TiO2 plot of the Tianba Flysch.There is a approximate linear relationship between Al2O3 and TiO2 in the analyses from the Tianba Flysch. PAAS from Taylor and McLennan (1985), basalt from Condie (1993).
Shales
Siltstone
Sandstones
TB5
Sediment Recycling (Zircon addition)
Compo
sitio
nal
varia
tions
Active margin
Passive margin
Figure 5.5 Th/Sc-Zr/Sc plot of the Tianba Flysch.Passive margin and Active magin fields, and trends of compositional variations and sediment recycling are from McLennan et al. 1990. PAAS from Taylor and McLennan (1985), average basalt composition from Condie (1993).There is a signficant enrichment of Zircon (high Zr/Sc) in passive margin setting resulting from sedimentary sorting and recycling.
128
PAAS
Basalt
Figure 5.6 Th/U-Th plot of the Tianba Flysch. Arrow indicates a weathering trend.Note analyses (except TB5) from the Tianba Flysch follow the weathering trend, similar to Australian Shales with cratonic provenance (McLennan et al., 1990). PAAS from Taylor and McLennan (1985), average basalt and granite compositions from Condie (1993).
130
Weathering Trend
Figure 5.7 Cr/V-Y/Ni plot of the Tianba Flysch.Note Cr/V ratios of the Tianba Flysch are constantly low with the increase in Y/Ni ratios.Mafic-ultramafic sources tend to have high Fe, Cr, Ni abundances with low Y/Ni and high Cr/V ratios. TB5 has high Cr and Ni abundances indicating a volcanic provenance. PAAS and Upper Crust from Taylor and McLennan (1985), average basalt composition from Condie (1993).
132
Oph
ioli
tic
inpu
t
Figu
re 5
.8 C
hond
rite
-nor
mal
ized
RE
E p
lot o
f th
e T
ianb
a Fl
ysch
, nor
th o
f T
ianb
a vi
llage
.A
ll an
alys
es e
xcep
t TB
5 sh
ow L
RE
E e
nric
hmen
ts a
nd n
egat
ive
Eu
anom
alie
s, s
imila
r to
PA
AS,
in
dica
ting
a co
mm
on c
rato
nic
prov
enan
ce. R
elat
ivel
y fl
atte
n R
EE
tren
d of
TB
5 po
ints
to a
sig
nfic
ant
volc
anic
sou
rce.
PA
AS
from
Tay
lor
and
McL
enna
n (1
985)
.
134
Quartzose SedimentaryProvenance
Mafic igneousprovenance
Intermediateigneousprovenance
Felsic igneousprovenance
Siltstone
Figure 5.9 Tectonic discriminant diagram for the Tianba Flysch.Tectonic setting fields are from Roser and Korsch (1988).F1=-1.773TiO2+0.607Al2O3+0.76Fe2O3-1.5MgO+0.616CaO+0.509Na2O-1.224K2O-9.09F2=0.445TiO2+0.07Al2O3-0.25Fe2O3-1.142MgO+0.438CaO+1.475Na2O+1.426K2O-6.86Data from Roser and Korsch (1988).
135
0.1TB6
Arc
ACM
PM
Figure 5.10 K2O/Na2O-SiO2 (a) and SiO2/Al2O3-K2O/Na2O (b) plots of the Tianba Flysch.Tectonic setting: PM-passive margin, ACM-active continental margin, ARC-volcanic arc, A1-Arc setting, A2-evolved arc setting (from Roser and Korsch, 1986).Most samples from the Tianba Flysch plot in the passive margin area while TB5 plots in arc or active continental margin, indicating a volcanic source for the upper Tianba Flysch. PAAS from Taylor and McLennan (1985).
138
K2O/Na2O
SiO
2/A
l 2O
3
Shales
Sandstones
TB5
Siltstone
PAAS
A1
A2
ACM
PM
ShalesSandstonesTB5SiltstonePAASK
2O/N
a 2O
SiO2 wt%
a
b
Gy
rong
-Kan
gmar
Thr
ust
Lha
sa B
lock
Indu
s-Y
arlu
ng T
sang
po-S
utur
e
Hig
h H
imal
aya
Nep
alB
huta
nY
adon
g
Kan
gmar
Tia
nba
Gya
ngts
e
Xig
aze
Gam
ba
Tin
gri
Lha
ze
100
km
India
Tet
hyan
Him
alay
a -
N
Tet
hyan
Him
alay
a -
S
Tib
etIY
ZS
Figu
re 6
.1 S
ketc
h ge
olog
ic m
ap o
f T
ingr
i reg
ion,
sou
ther
n T
ibet
. The
inse
t map
sho
ws
this
reg
ion
loca
ted
in th
e H
imal
ayan
sys
tem
. M
odif
ied
afte
r W
illem
s et
al.(
1996
).
Figu
re 2
142
Shenkeza
Youxia
Gongza
Section
28 42
28 44
28 40
86 42 86 44 86 46
Gongza
Shenkeza FM
Youxia FM.
Zhepure Shan FM.
Jidula FM
Pre-Jidula FMFault
Zhepure Shan Range
(1)
1 km
Figure 6.2 Simplified geologic map showing the location of the studied sections in the Tingri region on the western flank of Zhepure Shan Mountain. Note: (1) is measured section at Shekeza.Geographic coordinates in degrees, minutes.
144
Jidula Fm.: Calcareous and glauconitic sandstones intercalated with shales.
Zhepure Shanpo Fm.: grey and black marlstone, shale, and sandy limestones.
Zhepure Shan Fm.: Thick-bedded to massive limestones with abundant foraminifera, intercalated with calcareous marls and marls.
0 m
200 m
0 m
100 m
185 m
Shenkeza Fm.:Red mud rocks, siltstones and sandstones.
Youxia Fm.:Green shales and thin-bedded sandstones with rare limestones.
Zhepure Shan Fm.Limestones and marlstones.
Figure 6.3 Stratigraphic columns of lower Tertiary sequence in the Tingri region. The Shenkeza section was measured by us in 2000, and the Gongza section is from Willems et al. (1996). Section locations are shown in Figure 2. Sample locations are indicated by "Sxxx" at Shenkeza section and "Julxxx" at Gongza section.
Gongza Section Shenkeza Section
S87
S88
S90
S94
S95
Unconformity
marlstonequartzose sandstone/siltstone limestone shale
Jul75
600 m
800 m
Zhepure Shanbei Fm.: Well-bedded limestones interbedded with thin layers of calcareous marls.
Gamba Group: pelagic and hemi-pelagic marls and caclareous marls.
Jul2
Jul1
S138
S141
S145
S148
lithic arenites
50 m
S150, 151
150 m
145
Figure 6.4 View to E of the upper part of the Youxia Formation in the head of the Shenkeza valley, made up of green shales and sandstones. The shales conformably overlie the Zhepure Shan limestones. The section of the upper Youxia Formation was measured up the gully on the left side of the photo.
Youxia Formation
149
Zhepure Shan Formation
Shenkeza Formation
Figure 6.5 View to N of Shenkeza Formation of red shales and occasional intercalations of fine-grained sandstones. The Zhepure Shan limestones above are in thrust contact with this unit.
150
151
Figure 6.6 View to NW of the unconformity between the Youxia and Shenkeza Formations. Note there is abrupt change in color from green to red. Excavation of the contact at the location of the hammer in this photo revealed a 1 m thick soil horizon of the base of the red unit, and a rubbly regolith of green sandstone fragments below it. [Professor W. Kidd stands on the unconformity, 21 Oct 2000]
Figure 6.7 Hummocky cross-stratification in the top sandstones of the Youxia Formation, indicating a depostional environment of storm waves during the late Youxia Formation.
153
Qt
F L
Con
tinen
tal B
lock
Pro
vena
nce
Magmatic Arc ProvenanceR
ecyc
led
Oro
gen
Prov
enan
ceA Stumpata/Dibling
B Balakot Fm.
C Subathu Fm.
D Siwalik (Nepal)
B
Figure 6.8 Detrital mode plot of lower Tertiary sandstones in the Tingri regionTectonic fields from Dickinson, 1985. Fields of other related Himalayan sandstones shown are from Garzanti et al. (1996)
Qm
F Lt
Con
tinen
tal B
lock
Pro
vena
nce
Magmatic Arc Provenance
Recycled O
rogen
Provenance
Mixed
Jidula Sandstone Youxia Green Sandstone Shenkeza Red Sandstone
A
C
D
156
300 um
Figure 6.9 Photomicrograph (crossed polars) of quartz-rich sandstone (Jul2) in the Jidula Formation, Gongza section. Note: most quartz grains are well-sorted, unit extinguishing.
159
Figure 6.10 Photomicrograph of well-rounded monocrystalline quartz gains with calcite cement in the Jul 75 sandstone of Jidula Formation, Gongza Formation. Opaque minerals are magnetite or ilmenite.
300 um
160
100 um
Figure 6.11 Photomicrograph (crossed polars) of a metamorphic rock fragment in Jul 75 sandstone of Jidula Formation, Gongza section.
161
300 um
Figure 6.12 Photomicrograph (crossed polars) of lithic-rich sandstone (Shen88) in the Youxia Formation, Shenkeza section. Note most quartz grains are angular in shape.
162
100 um
Figure 6.13 Photomicrograph (crossed polars) of volcanic rock fragments in the Shen88 sandstone of the Youxia Formation, Shenkeza section.
Volcanic lithic
Volcanic lithic
164
Calcite
100 um
Plagioclase
Volcanic lithic
Figure 6.14 Photomicrograph (crossed polars) of Shen94 sandstone in the Youxia Formation, Shenkeza section. Note there are calcite, volcanic lithic and plagioclase grains.
Calcite
165
chertvolcanic lithics
100 um
Figure 6.15 Photomicrograph (crossed polars) of volcanic and sedimentary rock fragments in the Shen87 sandstone of the Youxia Formation, Shenkeza section.
166
QuartzCalcite
100 um
Plagioclase
Figure 6.16 Photomicrograph (crossed polars) of a plagioclase grain in the Shen94 sandstone of the Youxia Formation, Shenkeza section.
167
Quartz
Calcite
100 um
plagioclase
metamorphic lithic
Figure 6.17 Photomicrograph (crossed polars) of a broken plagioclase and a metamorphic rock fragment in Shen88 sandstone of the Youxia Formation, Shenkeza section.
168
Quartz
Figure 6.18 Photomicrograph (crossed polars) of angular-subangular greywackes (Shen145) of Shenkeza Formation, Shenkeza section.
200 um
169
200 um
Figure 6.19 Photomicrograph (crossed polars) of angular quartz grains and a plagioclase in the Shen148 sandstone of Shenkeza Formation, Shenkeza section.
170
Natural Waters
Plagioclase K-Feldspar
Muscovite
Illite
Kaolinite,Gibbsite, Chlorite
Pred
icte
d w
eath
erin
g tre
nd
Figure 6.20 CIA ternary plot of lower Tertiary clastics in the Tingri region. Modified after Bock et al. (1998). The enrichment in Al2O3 and depletion of CaO+Na2O+K2O on this plot reflects the degree of chemical weathering to which the materials have been subjected. Three analyses of the Jidula Fm. defined a linear trend encompassed in the predicted weathering trend for the average upper crustal composition while those of the Youxia Fm. do not follow the predicted weathering trend, indicating processes in addition to the weathering have affected the Youxia sediments.
Upper crust
Youxia ShalesYouxia/Shenkeza Sandstones
Jidula Sandstone
176
0
2
4
6
8
10
12
14
16
18
20
30 50 70 90
1
10
100
0.1 1.0 10.0
Figure 6.21 Geochemical plot of the lower Tertiary clastics in the Tingri region. a. Al2O3 vs. SiO2 plot; b. SiO2/Al2O3 vs. K2O/Na2O plot; c. Al2O3 vs. TiO2 plot; d. K2O/Na2O vs. SiO2 plot. Tectonic setting fields are from Roser and Korsch (1986) for Figure 6.21 d and PM is passive margin field from McLennan et al. (1990). Note in Fig 6.21d, Jul1 and Jul75 are recalcualted to 100% CaO and volatile-free because of signifcantly high CaO contents. PAAS from Taylor and McLennan (1985), basalt from Condie (1993).
Al 2
O3
SiO2
Youxia-Shales Youxia/Shenkeza-Sands
SiO
2/A
l 2O
3
K2O/Na2O
Jidula-Silt
Jidula-Sand
ba
c
Al2O3
TiO
2
SiO2
K2O
/Na 2
O
ARC
Active Margin
Passive Margin d
PM
Jul75Jul1
177
Basalt PAAS
Cho
ndri
te n
orm
lized
RE
E p
atte
rns
Youxia-Shale95
Youxia-Shale90
Youxia-Sand94
Shenkeza-Sand148
Jidula-Silt1
Jidula-Sand2
Jidula-Sand75
F1
F2
Quartzose SedimentaryProvenance
Mafic igneousprovenance
Intermediateigneousprovenance
Felsic igneousprovenance
Figure 6.21(continued). Geochemical plot of the lower Tertiary clastics in the Tingri region. e. Provenance discrimination diagram; f.Chondrite-normalized REE patterns, chondritic values are those of Taylor and McLennan (1985). Tectonic setting fields are from Roser and Korsch (1988) for Figure 6.21e. Note in Figure 6.21e, Jul1 and Jul75 are recalculated to 100% CaO and volatile-free because of signficantly high CaO contents.
e
f
Jul1
Jul75
178
A
B
CD
PM
Figure 6.22 Tectonic discrimination plots from Bhatia and Crook (1986): a. La-Th-Sc ternary plot; b. Th-Sc-Zr/10 ternary plot. Fields are A-oceanic island arc, B-continental island arc, C-active continental margin, D-passive margin. PM is the Passive margin field from McLennan et al. (1990).
Youxia/Shenkeza-Sands Jidula-Silt Jidula-Sand
a
Th
Zr/10Sc
b
PM
184
Continentalflood Basalt
Alaska-type
OphioliteOphiolites
Al2O3
TiO
2
S148 S94 S87 S88
CFBOIB
MORB
ARC
SSZ Peridotite
MORBPeridotite
20
30
40
50
60
70
0 10 20 30 40Al2O3
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
0.00.10.20.30.40.50.60.70.8Mg/(Mg+Fe2+)
Cr/
(Cr+
Al)
Fore-arc Peridotites
Xigaze Ophiolites
Luobusa Ophiolites
AbyssalPeridotites
JijalPeridotites
Ladakh Peridotites
Figure 6.23 Geochemical plot of Cr-rich spinels from the Youxia and Shenkeza sandstones. a. Al2O3 vs. Cr2O3 plot, b. Cr# (Cr/(Cr+Al)) vs. Mg# (Mg/(Mg+Fe2+)) plot, fields displayed are: Abyssal peridotites from Brindzia and Wood (1990), Fore-arc peridotites from Parkinson and Pearce (1998), Jijal Peridotites and Ladakh peridotites from Rolland et al. (2002), Luobusa ophiolites from Zhou et al. (1996), and Xigaze ophiolites from Wang et al. (2000). c. TiO2 vs. Al2O3 plot, fields displayed are from Kamenetsky et al. (2001): CFB-continental flood basalt, OIB-oceanic island basalt, MORB-mid-ocean ridge basalt, ARC-volcanic island arc, SSZ-suprasubduction zone. d. Cr-Al-Fe3+ ternary plot, fields displayed are from Cookenboo et al.(1997).
Cr 2
O3
Cr Al
Fe3+
a b
c d
188
Figure 6.24 Comparison of stratigraphic columns of the Himalayan foreland basin, from Hazara-Kashmir (Bossart and Ottiger, 1989, which is modified by Najman et al. (2002)), through Zanskar (Garzanti et al., 1987, 1996), Himachal Pradesh (Najman and Garzanti, 2000), to Tingri, southern Tibet (this study). Timescale after Berggren et al. (1995).
Yellow-mature clastics of Indian passive margin; blue-carbonates of the Indian passive margin; green-marine orogenic clastics; red-non-marine redbeds.
193
Thanetian
Ypresian
Lutetian
Bartonian
Priabonian
Selandian
Danian
61.0
57.9
54.7
49.0
41.4
36.9
33.7
Pale
ocen
eE
ocen
e
Epoch StageAge
(Ma)
Hazara-
Kashmir
Balakot Fm.
Lockhart Fm.
Patala Fm.
Zanskar
Chulung La Fm.
Dibling Fm.
Stumpata Fm.
Zhepure Shan Fm.
Jidula Fm.
Subathu Fm.(sandstones)
Subathu Fm.(limestones)
Himachal Pradesh (N. India)
Tingri
Youxia Fm.
Shenkeza Fm.?
?
?