Embed Size (px)
Citation preview
Metamorphic Rock Of Darab Related To Uranium Mineralization *
Retno Witjahjati, Soeprapto T., Manto W
Nuclear Minerals Development Centre, BATAN
Abstract
Metamorphic Rock of Darab Related to Uranium Mineralization. Metamorphic rock of Darabis surrounded and intruded by granitic rocks, which is composed of medium to fine pained, itidentified as phyllite interbedded with quartzite. Milimetric to decimetric vein structures whichdeterminated as biotite, quartz-biotite, andalusite, quartz -apatite, biotite-apatite, gypsum, tourmaline, quartz-orthoclase, and quartz have been found within the metamorphic rock. Metamorphicgrade of the rock is medium at near contact zone, while low grade metamomhism has been idp.n
tified away from the contact, it may indicate retrogade process has exist. Uranium mineralizationsoccurred in granite and metamorphic rock as well, as brecia fillings or veins at the contact vicinities. Radioactive minerals have been identified as uraninite and monazite, they are mostly associated with magnetite, ilmenite, molybdenite, ilmenorutile, sphalerite, pyrite, arsenophyrite,biotite, tourmaline'oapatite, tnd quartz. Formation of the mineralization were interpreted to bemesothermal at 300 C to 600 C with granite as the bearer.
INTRODUCTION
This paper is a result of a mineralogical study on Metamorphic Septa of Darab,West Kalimantan. Knowledge were obtained from the study is expected to explainhow the metamorphism process contributes to the uranium accumulations. The knowledge would support someways in developing exploration programmes of Schwanerregion.
Geological data has been gained from those study includes morphology, lithology,structure and radioactivity of outcrops which measured by scintillometer SPP2-NF isaround (400-15000) count per second (cps).
Metamorphic rocks which have been discovered in Darab was intruded by graniticrocks. The intrusion is probably occured in Cretaceous magmatic period [1]. Fieldobservation shows that metamorphic rocks consist of fine grained materials whichexhibite some relict of sedimentary structures, i.e. lamination and bedding planes.
Uranium mineralization veins were discovered mostly as tectonic breccia fillingor sulphide associated veins within granite and metamorphic rocks.
*Presented in Joint Indonesia - German Seminar on Uranium Exploration, Geology andExtration, Jakarta, October, 16 - 18,1989.
13
MATERIALS AND METHODS
Mineralized and unmineralized rock samples have been taken from the interestarea, both of igneous and metamorphic rocks (Fig. 2). These samples were analyzedmicroscopically by using petrography, and mineragraphy methods.
Data collected from the analysis include mineral composition, texture, and kindsof the rock. D, Th, Sn, W, and Mo content have been obtained from selected samplesusing Atomic Adsorption Spectrometer, Major oxides content in the rocks are derivedfrom mineral composition of modal analysis which is calculated based on theoriticaloxides content in minerals propose by Deer, et.al [2] , (Table 5).
Relationship between uranium mineralization, host, and the source would be in
terpreted from the petrograph!c and mineragraphic data and also from their chemicalcompositions.
RESULT AND DISCUSSION
Geological Setting Of Darab
The studied area is a part of the Southern slopes of Schwaner Mountains range.Regionally, it consists of tonalite which supposes to be anatexis origin from gabroicand andesitic tuff formations [I]. Tonalite is overlied by metamorphosed rock whichconsists of sericite schist, biotite-sericite phyllite, volcanic, and often contains carbon
aceous materials. Migmatitic texture occured in some part of rocks as granitic gneissand migmatitie. Those rocks are probably the transition phase between metamorphicand plutonic stages.
Geological observation of the metamorphic septa of Darab shows that this rockis surrounded by granite, so the structures look like a "roof pendant" of the graniticbatholith or a relict or anatexis metamorphic rocks [3] (Fig. 3).
Metamorphic rocks mostly composed or fine grained, of sandy to silty materialssuch as phyllites with some quartzite interbeds. Milimetric to decimetric veins ofbiotite, tourmaline, quartz, and gypsum have been discovered.
Metamorphic Rocks Of Darab
Lithologically, the metamorphic rocks consist of phyllite and low grade quartzite.
Phyllite
Phyllite covers mostly the studied area. It usually shows light to dark grey colors,0:01 mm - 0.3 mm grain size, and some times a relict of the stratifications and laminations. Petrographically, the rocks compose of quartz, sericite, biotite, andalusite,cordierite and opaque minerals. Orthoclase, tourmaline, monazite, apatite, epidote andzircon as accessory minerals have often been found.
Alteration process such as silicification, sericitization, and chloritization has beendetermin~d from mineralized zone samples.
Spotted slate structures are also obserVed in some samples (MW 52, MW 125, SWO97, MW 106 and MW I] 3). The structures conta!n of agregates of sericite, andalusite,cordierite, biotite minerals in quartz and sericite matrix.
14
Severa] veins which were identified microscopically in the thin section consist ofbiotite (SWO 185), quartz-biotite (SWO 89, SWO 97, DW 20), andalusite (MW 70),quartz-apatite (MW 52), biotite-apatite (MW 125) and gypsum (SWO 185).
The occurrences of andalusite and apatite minerals may indicate a high tempera-'ture veins, while the agregation and impregnation textures of tourmaline, biotite,monazite, and opaque minerals indicate metasomatic injection.
Quartzite
Quartzites are exposed in a relatively small area. They show light grey colour,massive structures, compact but some of them show a relict of stratifications.
Petrographically, the quartzite shows granoblastic with equigranular texture,0.0 I nun - 0.2 mm grain size. Mineral composition is quartz, sericite, biotite, tourmaline. a little of epidote, and muscovite. Zircon, monazite, apatite and opaque mineralshave been identified 'as accessory minerals.
MicroscopicaJly, several veins also can be identified in thin sections. The veins
consist of tourmaline (SWO 90, SWO 25 B), biotite (SWO 25 B), quartz-biotite(SWO 89), quartz-orthoclase (DW 20), granite (MW 1.15), granodiorite (MW 9) anddypsum (SWO 61).
Metamorphic Origin
Value of A, C, F, A' and K have been calculated from Winkler's formula [4]:A = (A1203 + Fe203) - (Na20 + K20)
C = (CaO - 3.3 x P205)
F = MgO + FeO + MnO
A' = (A1203 + Fe203) - (Na20 + K20 + CaO).K = K20
Based on the position of A, C, F, A I, and K parameters of the rocks which havebeen plotted to ACF and A' KF of Winkler's diagram, origin of the metamorphic rockscould be interpreted.
Calculation of ACF and A' KF values of phyllite and quartzite samples based onthe theoritical oxides content in mineral of rocks (Table 6, 7). These values plotted toACF and A' KF diagrams (Fig. 4), from the sample position plots, can be interpretedthat the phyllite and quartzite are originally from claystone and greywacke sediments.
Metamorphic Type and Grade
Petrological and petrogaphical observations on metamorphic rocks in field and -thelaboratory show granoblastic texture, poor foliation, spotted slate, and some relict oftheir stratifications.
15
Petrographic criteria of Darab metamorphic rock may indicate that thermal factor has higher influenced than pressure factor. According to those, magmatic intrusion process possibly produces a contact metamorphic zones at the adjacent rock [3] .Andalusite and cordierite minerals which have been found in several parts of rockindicate a contact metamorphism process on medium grade. The reaction are [4] :
Ch!orite + Muscovite + Quartz --:). Cordierite + Biotite + Andalusite + H20
Muscovite + Quartz ~ K. Feldspar + Al2Si05 + H20
Chloritization and serisitization of andalusite and feld spar which usually exist insome samples may indicate that some retrograde metamorphic process has been occured. However, metamorphic rocks in the region as overall view is a low grade metamorphism.
Uranium Mineralization In Darab
Uranium mineralization occured as a mineralized out crops both in granite andmetamorphic which closed to the contact as tectonic breccias filling, veins, or metamosmatic contact [5]. Milimetric to decimetric of tectonic breccias are generallycontrolled by N 1300 E to N 1600 E tectonic activity. Radioactivity values of themineralized outcrops are about 400 to 15000 cps SPP 2 - NF.
Mineral paragenesis of mineralized samples are magnetite, ilmenite, ilmenorutile,uraninite, molybdenite, hematite, sphalerite, pyrite, arsenopyrite (Table 2), and itsfollowed by development of brokite, chalcopyrite and bornite-as a second stage theparagenesis (Table 3).
Radioactive minerals in the mineralized rocks are uraninite or may be some thorian-uraninite, that exhibit rimed textures of iron sulphides [3,6] . Uranium bearingmonazite and opaque minerals have also been identified and they have caused anoccurence of pleochroic halo structures in associated biotite.
Uranium content of the mineralized zone is quite high, the maximum content isabout 0.2141 %. Th/U ratio relatively low. Molybdenum element exist in almostsamples were analyzed, but stanum and wolfram are un significant (Table 4).
The formation temperature is about 3000 - 6000 C and it was interpreted as
magmatic origin due to their elements and minerals content.
Relationship Between Metamorphism Process And The Mineralization
Uranium mineralizations occurred mostly in West part of Metamorphic Speta of
Darab, they are exposed relatively near the contact between metamorphic rock andgranitic body. Some mineralizations associated with granitic veinlets which commonlydiscovered at along the contact zone. Uranium minerals in them are uraninite, pro
bably thorian bearing uraninite. Microscopically, the individual uraninite associatedwith iron sulphides and iron oxides.
16
Based on the mineral association and textures, formation of the mineralizations
related to the granitic intrusion and contact metamorphism process.
CONCLUSION
Metamorphic Septa of Darab consists of a low grade metamorphic rockswhich could be determined as phyllite and quarzite. They are originally from clay
stone and greywacke sediments.Granitic intrusion which has been formed from the magmatic activities
during the Cretaceous period may have strong influenced the metamorphic grade ofthe contact vicinity between intrusion and metamorphic rocks.
Uranium minerals occurred as uraninite or thorian uraninite which crysta
llized from highly differenciated granitic magma were deposited in tectonic breccias,granicit veinlets and in metamorphic rocks closed to the contact at 3000 C - 6000 C.
ACKNOWLEDGEMENT
We would like to thank Mr. Djodjo as Head Exploration Divison for providing thefacilities and advices. Also, particularly gratitute to our colleagues in Mineralogy SubDivision. who generaly help until this paper completely written.
REFERENCES
1. COMMISARIAT A L'ENERGIE ATOMIQUE (CEA) - BATAN "Overseas MineralExploration, Indonesia: Project Kalan." RSI 68, (1976)
2. W.A. DEER, R.A. HOWIE, J. ZUSSMAN. "An Introduction to the Rocks Forming Minerals". The English Language Book Socitey and Longman (1985)
3. SOEPARTO. "Studi Mikroskopik Contoh Batuan Zona Mineralisasi UraniumSektor Darab. Kalimantan Barat". PPBGN-Batan (1985)
4. H.G.F. WINKLER. "Petrogenesis of Metamorphic". Springer-Verlag, Berlin,Heidelberg, New York (1976)
5. PPBGN-BA TAN. "Laporan Prospeksi Superdetail, Sektor Darab, Kalimantan(1988). (unpublished)
6. G. D'ARCY. "Mineralogy Uranium and Thorium Bearing Minerals". Raw materialoperation office, Washington 25 DC. (1949)
7. H. WILLIAMS, F.J, TURNER and C.M.GILBERT." Petrography an Introductionto the Study of Rock in Thin Section". W.H. Freemon and Co, San Francisco(1958)
8. H.G.F.WINKLER." Petrogenesis of Metamorphic". Springer - Verlag, Berlin, Heidelberg, New York, (1976)
9. A. SPRY. "Metamorphic Texture". Pergamon Press. Oxford, New York, Toronto,Sydney, Paris, Frankfurt. (1976)
17
- 00
Tab
leI.
Pet
rogr
aphi
cA
naly
sisI
of
Met
amor
phic
Roc
k
Sam
ples
No.
SWO
.18
5SW
O.
197
SWO
.18
9SW
O.
206
MW
.70
SWO
.90
SWO
.76
Rad
iom
etry
125
cps
120
cps
500
cps
130
cps
i50cp
s14
0cp
s15
0ep
sR
ock
Nam
eK
MB
BM
QFo
liatio
n-B
QFo
liatio
n-B
MQ
Met
asilt
Met
asilt
Met
asilt
Mic
rosc
opit
I11
I11
II
I11
I11
I
Qua
rtz
15,6
315
.84
6.71
40.3
715
.63
41.6
237
.31
5.03 57
.55
35.6
1B
iotit
e38
.06
36.9
133.
6252
.06
-10.
875.
7712
.52
-8.9
3T
ourm
alin
e-
- 0.35 0.95
-20
.76
56.7
111
.31
Zir
con
-- 0.01 0.
28---
Mon
azite
5.47
0.35
-0.
20-
0.11
-Se
rici
te32
.38
30.4
26.
3839
.96
32.1
3-
20.0
6M
usco
vite
--
37.4
4 -8.
06-
7.16
And
alus
ite-
-4.
03 -15
.43
60.7
1--
Epi
dote
-- 1.17 2.
32---
Alla
nite
--- --
1.23
-A
patit
e1.
506.
022.
02-
--8.
037.
97-
Chl
orite
--
17.3
0-
-3.
1010
.29
10.8
9Pl
agio
clas
e-
-- --5.
05-
Ort
hocl
ase
--
10.9
6-
---M
icro
clin
e-
-- ----O
'paq
ueM
iner
al2.
5335
.76
0.84
5.20
1.31
3.80
1.30
21.7
44.
0625
.03
5.05
Iron
are
--- -- ---
Clin
ozoi
site
--- -- --
Cor
dier
ite-
28.4
15.
42-
- ---N
ote
./.Fo
liatio
n,.1
.'F
Dlia
tiol1
,L
amin
atio
n,m
ag·
Hor
nfel
sU
ndis
tinet
folia
·/.
Gra
nobl
astic
,H
ornf
elsi
cO
.Olm
m-
0.03
mm
porp
hiro
blas
ticm
atic
inje
ctio
nO
.OJm
m-
0.03
mm
tion
.0.
05m
m·
O.3
mm
porp
hiro
blas
tic,
Mus
covi
tera
diar
Lam
inat
ion.
II.
Vie
nw
ithte
x-m
atri
xO
,Olm
m-
11.
Segr
egat
ion
ofQ
uart
zgr
anul
arSe
greg
atio
nbi
o·tu
reho
locr
yst:I
ine
0.03
mm
,po
rfir
o-11
.V
ien
0.06
mm
biot
itetit
ew
ithha
los.
bIas
(0.2
-0.5
)m
mB
iotit
e's
halo
0.5
mm
Chl
orite
vein
cont
act
with
Hal
osin
.bio
tite
Bio
tite
vein
.m
onaz
ite
cont
act
with
mon
azit
e.M
icro
scop
ic
I.B
iotit
ese
rio
I.B
iotit
eco
rdie
·M
igm
atite
Seri
cite
-I.
Seri
cite
quar
tzI.
Qua
rtzi
teSe
rici
te-
cite
phyl
lite
rite
phyl
lite.
quar
tzite
phyl
lite.
quar
tzite
.II
.B
iotit
eve
inII
.A
ndal
usite
II.
Tou
rmal
ine-
Gyp
sum
vein
.ve
in.
vein
.
I
- \0
Tab
le2.
Min
eral
ogra
phic
Ana
lysi
sof
Ore
Sam
ples
ow
swo
swo
swo
swo
swo
ow
ow
SASow
ow
ow
SWOMW
MW
MW
SWOow
SarripleNo.
93
158
24
25A3
27
611547121
25
56115124
131
192
66
Radiometry
9000
1500
3000
1500
3000
2000
7500
2000
1500
140
3500
3000
600
5000
900
4000
3500
4000
Minerals.
cps
cps
cps
cps
cps
cps
cps
cps
cps
cps
cps
cps
cps
cps
cps
cps
cps
cps
Mag
netit
e
1--- ·2 5--- 0,5 2--- 1 ---
Ilm
enite
-1
4-- 3 433-1 5-5 -5 -3 -
Hem
atite
"20
12-10 2-------- 12 ---
Ilm
enor
util
--- 2 ------- 1 ------
Rut
il-
--- 1 -1 10.5--- 0.53
0.5-- -
Ura
nini
te-
-- 2 3-3 0.5-- 4 -- 2 -- 4 -
Mol
ybde
nite
----- ----- 12 ----- --
Pyri
te1
-- 15 -- 10 10-- 10 0.5-5 -- 2 10
Phrr
hotit
e
--- ---------- -- 1 -2
Ars
enop
yrite
-2 --------- -- --- 25 -
Spha
leri
te
-2 -- 3 ------ ----- 1 -
Ca1
copy
rite
--- 7 -- 3 -1 ---- 1 -2 -5
Bor
nite
----------------- 0.5
Bro
okite
---------- 0.5 -------
Lig
htM
iner
als
779198747
887 7985.5
98'.5
98.5
64.5
98.5
9489 81.5976582
.5
Table 3. Ore minerals paragenesis of Darab
MineralsPhase IPhase 2
Magnetite
--Ilmenite
--Ilme noru tile
--Rutile
--Uraninite
--Hematite
---Molybdenite
--Sphalerite
--Pyrite
--Arsenopyrite
--Brokite
--Bornite
--Chalcopyrite
--
Table 4. Element Content in Rock.
No.Samples No. UThSnWMoTh/U
I.
SWO-3 0.04390.0973NONO0.10842.240
2
SWO-25/A 0.1157NONONO0.0111 -3.
OW-61 0.17770.0139NO0.00410.08600.080
4.
OW-21 0.21410.0033NONO0.26620.010
5.
MW-115 0.11860.OQ91NONOTD0.070
6.
OW-2 0.000657NONONO0.000667-
7.
OW-42 0.000606NONONO0.000167-
8.
OW-15/AB 0.001364·NONONO0.000333-
9.
SWO-39 0.000657NONONO0.000333-10.
SWO-160 0.000455NONONO0.000333-
II.OW-64/A 0.000550NONONO0.000333-
20
to.) -
Tab
le5.
Osi
deC
onsi
sten
tin
Min
eral
(How
ie's
)
Min
eral
com
po
Ort
ho-
To
urm
a-M
ona-
Opa
nue
Qua
rtz
Bio
tite
Seri
cite
Lep
idol
iteC
hlor
itePl
agio
clas
eE
pido
teA
llani
teA
patit
eA
ndal
usite
Cor
dier
iteZ
irco
ncl
ase
line
zite
Oxi
deca
nst.
SiO.
99.5
39.1
448
.42
49.8
025
.61
64.7
163
.66
36.3
61.
4036
.92
30.3
2-
36.7
4 49.4
632
.51
0.27
TiO
,
-4.
27 0.87-
0.88 ----- 0.04 -0.01 0.
01---
A1,
O,
-13
.10
27.1
625
.56
21.1
922
.66
19.3
440
.48
-22
.25
15.1
9-
62.7
0 33.5
80.
210.
21
Pe,0
,
-12
.94 6.
570.
083.
880.140.10-
-15
.21
3.77-0.36 0.
140.
0868
.85
FeO
-5.
05 0.81-
21.5
5 0.17-
3.64 -0.57 10
.81
0.260
.05
2.12-
30.7
8
MnO
-0.
14 -0.38
0.35--
1.05
-0.75
6.06
5.32-0
.08 --
MgO
-12
.75 -0.2
215
.28
0.25-
0.09 -- 0.32 0.040.0
312
.06
0.01
-C
aO'
-1.
64 -- 0.16 3.26 0.50
0.67
-23
.11 4.28
50.3
10.0
20.
030.
22-N
a,O
-0.
70 0.3
50.
40-9.86
0.80
2.20
--- --0.
14 --K,O
-6.
55 11.2
39.67-0.05 15.6
00.
44--- - 0.
07---
F
-1.
11 -6.85 -- - 0.10
---3.
41----
Bz0
,
------
-10
.30 --- -----
Liz
O
-- ----
-1.
27 ---- -- --
PzO
.
-- --
29.2
8 --41
.50-- --
Cez
0,
----- -- -
31.3
8 -------
(La,
Di)
z!;)
---- --
--30
.88 -------
ThO
,
------
--6.
4~ -------
V,O,
------
- ----- -- -
.-
YzO
,
------
----- --- --
Laz
O,
----- -
- -------.--
ZrO
------
--------
67.0
2 -
N N
Tab
le6.
Exa
mpl
eof
Oxi
des
Mol
ecul
eW
eigh
tCal
cula
tion
ofM
etam
orph
icR
ocks
No.
SWO
197
(Cor
dier
ite
biot
ite
phyI
ite)
.
Min
eral
sT
otal
wei
ght
%Q
uart
zB
ioti
teSe
rici
teC
ordi
erit
eO
paqu
eM
iner
alT
otal
wei
ght
(5)
wei
ght
Cor
rect
ion
Mol
ecul
e
Oxi
deco
nst.
(100
%)
SiD
,
99.5
xO.0
67~6
.97
39.1
4xO
.34=
13.3
1.4
8.4
lx.O
.30,
;,14
.53
.49
.46x
O.2
8.",
13..8
50.
27xO
.01~
0.00
248
.662
48.1
68'4
8.16
8:60
~0.8
.03
TiO
,
4.27
xO.3
4=1.
450.
87x0
.30=
0.26
0.0I
xO.2
8=0.
002
-1.
712
1.69
51.
695:
80~0
.021
AI,
O,
13.I
OxO
.34=
4.45
27.1
6x0.
30=
8.15
33.5
8xO
.28=
9.40
0.2I
xO.0
1=
0.00
222
.002
21.7
7921
.779
:10
2=0.
214
Fe,O
,
12.9
4xO
.34=
4.40
6.57
x0.3
0=1.
97O
.14x
O.2
8=0.
0468
.85x
O.0
1=0.
687.
097.
018
3Q'H
XJx7
.018
=21
052.
105:
160~
0.01
3
FeO
5.50
x0.3
4=5.
840.
8Ix0
.30=
0.24
2.12
xO.2
8=6.
5930
.78x
O.0
1=0.
316.
986.90
970
{100
x6.9
09=
4386
4.83
6:72
~0.0
67
MnO
0.14
x0.3
4=0.
05-
0.08
xO.2
8=0.
02 -0.
070.
069
0:06
9:71
=0.
00I
MgO
12.7
5x0.
34=
4.34
-12
.06x
O.2
8=3.
38-
I7.
727.
642
7.M
2:40
=0.
191
CaO
.
1.64
x0.3
4=0.
56-
0.03
xO.2
8=0.
008 -
0.56
80.
563
0.56
3:5
6~0.
0I
Na,
O
0.04
x0.3
4=0.
0I
0.35
x0.3
0=0.
10.
14xO
.28=
0.03
-0.
140.
138
0.13
8:62
=0.
002
K,O
6.55
x0.3
4=2.
2311
.23x
O.3
0=3.
370.
30xO
.28"
,0.
10-
5.70
5.64
35.
643:
94~0
.06
I'
I.llx
O.3
4=0.
38-
.-- 0.38
0.3
760.
376:
44~0
.008
P,O
,
A C I' A'
K F
(0.2
14+
0.01
3)-
(0.0
02+
0.06
)=0.
215
==
}o44
(0.0
1-
3.3
x0)
=0.
01=
=}o
20.
191
+0.
001
+0.
067
=0.
259
==
~54
(0.2
14+
0.01
3)-
(0.0
02+
0.06
+0.
01)
=0.
025
=~~
480.
06=
=~
2
0.25
9=
=)
50
\
t.J IN
III
Tab
le7.
AC
Fan
dA
'KF
Val
ue
SWO
197
SWO
97SWO
185MW
70
DW
20
MW
9
A
44
83.7
83
82.9
]8
14
C
20.3 1
1.570
F
54
1616
15.6
7586
A
48
7319
65 100
K216 24
1115
10
F
50
11 57
137590
Fig. 1. Situation map of Darab
24
_____ -,_n_
/
o 0.1 o~ Of> 0.8 1 i<rn,-SWQ. 39
()
•o1'1
Sc air
Somplf' numb~r
roe Ir (lurllpl.l (. rllllll".I,
lrtlo:tllullt," of nl!lri •. vnhl4l11
t-ttn~ral Qrap~;c QnolY5i~
Fig. 2. Location map of sample analysis
25
lliE!:'!J: E!JGrQnth
[=':::1M.• IQ,illE::-:lGrt1nntfinrit.
G'-=';JPhylili.
EJJ.pirtot:Cr onitp
1:::::··0:1
Q.uartziteIh-ITonolih
~qAdO",qllit"
~ 01--9' 0.6Sc oleo
08 1 Km.-
13
Darab_ I~A ~ I _ --_:-.':~_J::. ~.•-::..... _""T .. _ .._._':._ .. ~._... __.no'" •• " _
.... -- , t f,'11 '.1'; lieu.'. MnIMIr.~I. ,.•
~i.ratilicntlo,.. •.......•V .
Foliation \-/
OOl..ll'ldary of liiholoqy
rOillt
1111 e rol ",I',llltll
Anti,II",. (I.ls
Syn'hf'lf' ad"
'.\ ........ _.:, ."
. ~.:. --=-,r. ,....:.''\~\"', ~-=-":II •• -
Fig. 3. Geological map of Darab
26
'J ~I:
~ lonul dc'S
'~ r~((Jno(!i0ri\{':;
..A Lulc - (jll\d[; cJrufl,tt':)
v /',[}..;(!! ~{rC1n ill'S
FI\.:ld of (Jrt') ..'•.•..(Jckt'~
Cloys
•. :J J Cont inc'n\cll c loy~; 0f tr\l,:{rdl~ I((j! bt:! t
.•••o'.!~1(J(;r'L· Cluys
ACFA' KF
1.
SWO197 Clay Clay2.
SWO97 AI-rich ClayClay3.
SWO185 AI-rich ClayClay4.
MW 70 AI-rich ClayClay5.
MW 20 Greywacke6.
MW 9 Greywacke.
Fig. 4. Plot of chemical composition calculated from modal analysis of Darabmetamorphic rocks on ACF and A'KF diagram of winkler
27
