Transcript New insight on the geology of the Kuwait Group- Jal Al

New insight on the geology of the
Kuwait Group- Jal Al-Zoor
Escarpment- Sabah Al Ahmad Natural
Reserve, Kuwait
Alham Al-langawi
PAAET- Science Department
College of Basic Education- Kuwait
This Research was based on
Fieldwork investigations and sampling
 Petrographic study by polarizing
microscope and SEM
 Cathodoluminecence
 XRF
 Icpms
 Probe analysis
 Carbone and oxygen isotope analysis

Geology Of Kuwait For Jal Azoor Escarpment
based on Previous Studies
Group
Formation
Pleistocene
Dibdibba
Kuwait
Group
Lower
MioceneOligocene
Eocene
Alhassa
Fluvial
Include marine beach deposits,
sabkha and mud flats
sediments, alluvial and fluvial
sediments
Disconformity
Holocene
Lower-Middle
Miocene
Description
Conglomerates, gypsum
cements
Upper Miocene &
Pliocene 8.6 Ma ?
Disconformity
Lower
Fars
Calcareous fine sandstones, Coarse
sandstones, marly limestones, red
and green mudstones, sandy
Limestones (30-35 m)
Ghar
Coarse Quartz Arenites, sandy
limestones, marls and green
Mudstones (only 20 m exposed)Disconformity
Dammam
Marine
Age
Dolomitized limestones with
Chirt
Field Observations
Disconformity between
first (Dibdibba Fm.) and
second (lower Fars Fm.)
Sharp Contact
Undulating Contact
Burrows and Plant Roots
Plant roots
Burrows
Plant roots
Burrows
Burrows
Cross-Bedding
Graded-Bedding
Change in current Velosity
Ripple Marks- Depositional
Paleosoil leaching
Nodules
Exposure surface marked by
conglomerates
Nodules
Exfoliation- Weathering
Gypsum Cement
Joints  Frost Wedging
Weathering
Geodes- diagenetic
Mega Fossils
Coiled Gastropods
Oysters
Coiled Gastropods
Bivalves
Gastropod
Marker Beds
Marker Bed (1)
Disconformity
Marker Bed (1)
Marker Bed (1)
Marker Bed (1)
Marker Bed (2)
R11
R1
R20
R2
R12
R13
R3
R21
R14
North
West
R4
R32
R5
R33
R22
R15
R34
R6
R16
R65
R17
R7
R8
R23
R9
R36
R10
R38
R66
R69
R24
R58
R39
R67
R68
North
East
R35
R18
R19
South
West
Fossils
R37
Burrows
R40
Exfoliation
Geodes
Pebbly Sandstone
Cross-Bedding
Cross-Bedded
Limestone
Fractures
Gypsum cement
R59
R54
R25
R53
R26
R27
R55
R28
R56
R29
R30
R31
R64
R57
29.43
29.42
29.41
29.4
29.39
29.38
29.37
29.36
29.35
29.34
Northeast
Northwest
29.33
29.32
29.31
29.3
Reservation
Gate
Southwest
29.29
Sabah Al-Ahmad natural
reserve northwest of
Kuwait bay (330 km2)
29.28
29.27
29.26
47.4
47.41
47.42
47.43
47.44
47.45
47.46
47.47
47.48
47.49
47.5
47.51
47.52
47.53
47.54
Petrography
Rock Types








Pebbly Sandstones
Fine Sandstones
Paleo-soils
Fossiliferous sandy Grainstones
Fossiliferous oolitic-sandy Grainstones
fossiliferous oolitic-sandy Packstones
Fossiliferous Mudstones
Peloidal sandy Packstones
Rock Types
Fossiliferous Sandstone 2X
Packstone 4X
Packstone 2X
Peloidal limestone 2X
Fine Sandstones with Poikilotopic Cement
4X
2X
4X
2X
Rock Types
Carbonate Fossiliferous
Mudstone 4X
Oolitic Grainstone
Oolitic-peloidal Grainstone 2X
Sandstone (paleo-soil)
Fossils
Mollusks (Bivalves and Gastropods), some
are oysters
 Coral fragments
 Coralline algae
 Foraminifera
 Echinoderm Plates
 Bone fragments

Fossils
Bivalves 2X
Foraminifera 4X
Corals 2X
Coralline algae 4X
Fossils
Echinoderm Plate with
syntaxial cement 4X
Foraminifera 2X
4X
Corals 4X
Fossils
Foraminifera
Cements
Isopachous and Spary calcite
4X
Poikilotopic Calcite
Cements
Spary and microcrystalline calcite
Poikilotopic Gypsum
Spary and
microcrystalline calcite
2X
Matrix
Clay Matrix
Clay Matrix
Carbonate Matrix
Matrix
Matrix
Geochemistry
Southwestern location
50000
40000
30000
2
Al
3
4
20000
1
2
10000
0
70
60
50
40
30
20
Fe
4
K
5
Mn
6
6
MgCO3
Na
7
P
8
9
9
9
8
8
7
7
10
0
6
3
4
5
CaCO3
5
1
1
2
3
ppm
Mole %
First location toward the East
1
30000
25000
20000
4
Fe
5
K
6
Mn
7
Na
8
P
9
10
15000
3
Al
8
10000
2
3
5000
1
1
0
40
35
30
25
20
15
5
MgCO3
9
10
0
CaCO3
9
10
10
7
7
8
6
6
4
4
5
5
2
3
ppm
Mole %
2
Second location toward the East
40000
3
4
30000
Al
Fe
4
2
3
20000
1
3
10000
0
90
80
70
60
50
40
30
20
0
K
5
MgCO3
Mn
6
Na
7
P
8
9
9
9
8
8
7
7
6
6
5
5
10
2
CaCO3
2
4
1
1
ppm
Mole %
Eastern Location
1
2
2
3
3
Al
4
Fe
5
K
6
7
Mn
8
Na
9
P
10
9
70000
60000
50000
40000
30000
20000
10000
0
90
80
70
60
50
40
11 12
11
30
10
20
0
MgCO3
7
10
CaCO3
12
12
6
5
8
6
7
8
9
10
11
5
3
4
4
1
2
ppm
Mole %
1
Elements Concentration Maps
Fossiliferous -sandy limestone
Al
Si
Mg
Mn
Ca
Elements Concentration Maps
fine sandstone with Poikilotopic cement
Al
Si
Mg
Mn
Ca
Elements Concentration Maps for
Peloidal-oolitic sandy- grainstone
Al
Si
Mg
Mn
Ca
Elements Concentration Maps-clay Matrix
Al
Si
Mg
Mn
Ca
Cathodoluminesence

First diagenetic calcite is with brownish-red
luminescence

Second diagenetic calcite is zoned isopachous and
spary crystals with yellow, orange, and non -
luminescent zones

Third diagenetic calcite is zoned spary crystals with
pale blue and non -luminescent zones

Forth diagenetic calcite show yellow-orange
luminescence
First and second diagenetic calcite in limestones
10X
4X
Second diagenetic spary calcite crystals
In Limestones
10X
In Sandstones
Third diagenetic calcite is zoned spary crystals
with pale blue and non -luminescent zones
3rd
3rd
3rd
10X
Forth diagenetic calcite (found in Paleo-soils)
4X
Collecting special parts for
Isotope Analysis
Oysters
Carbon13 and Oxygen18 Distribution for Kuwait Group
Normal Marine
Isotopic Values ?
18
O
-11.00
-10.00
-9.00
-8.00
-7.00
-6.00
-5.00
-4.00
-3.00
-2.00
0.00
-1.00
0.00
-1.00
-2.00
High Temperature
Fresh water
-3.00
-4.00
-5.00
-6.00
-7.00
13
whole limestones
shells
whole sandstones
Spary cements
C
0
-1
-2
-3
-4
-5
-6
-7
-8
-9
-10
-11
Carbon13 and Oxygen18
Distribution for Kuwait
Group With depth
R12
D18O
R15
R16
R18a
R19
D13C
Sample Number With Depth
R13
Variation in Carbon13 and Oxygen18 concentrations
within Marker Bed 1 (Grainstones and Packstones) from
West to East
Marker Bed 1 (Limestone)
0.00
-1.00
-2.00
-3.00
-4.00
-5.00
-6.00
-7.00
-8.00
-9.00
-10.00
Southwest
D13C
D18O
Notheast
Conclusions

Fieldwork and petrographic data
support the idea of several Depositional
environments for the Kuwait Group,
which are:
1. Mixed clastic-carbonate shelf
2. High energy beaches
3. Fluvial-marine , which may be delta
complex
4. Terrestrial environments- soil horizons

Fieldwork and petrographic data support the
idea of several unconformity surfaces within
the Miocene-Oligocene Kuwait Group which
were identified by:
1.
2.
3.
4.
5.
6.
Karst surfaces
Ripple marks
Nodules baring levels
Paleo-soils
Calcified plants roots
Reworked (conglomeratic surface)
Dibdibba Fm
(Pleistocene)
Paleo-soil
Roots
Lower
Fars Fm.
Paleo-soil
Paleo-soil
Paleo-soil
Roots
Roots
GharFm.
Fm.
Ghar

Carbone13 and Oxygen18 isotopes indicate
digenesis under high temperature fresh water
for all the formations which was supported by:
1. Depleted Carbone13 values (-3.70 to -6.59)
2. Depleted Oxygen18 values (-6.69 to -10.06)
3. Calcified plants roots

(plant decay  organic carbon)
4. Paleo-soils
5. Karsts surfaces
Thank you for sharing
this time with me
Photo by Alham Al-langawi