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GeoArabia, Vol. 6, No. 4, 2001Gulf PetroLink, Bahrain
573
Tectonic and Geologic Evolution of Syria
Graham Brew and Muawia Barazangi, Cornell UniversityAhmad Khaled Al-Maleh, Damascus University
and Tarif Sawaf, Syrian Petroleum Company
ABSTRACT
Using extensive surface and subsurface data, we have synthesized the Phanerozoic tectonicand geologic evolution of Syria that has important implications for eastern Mediterraneantectonic studies and the strategies for hydrocarbon exploration. Syrian tectonicdeformation is focused in four major zones that have been repeatedly reactivatedthroughout the Phanerozoic in response to movement on nearby plate boundaries. Theyare the Palmyride Mountains, the Euphrates Fault System, the Abd el Aziz-Sinjar uplifts,and the Dead Sea Fault System. The Palmyrides include the SW Palmyride fold andthrust belt and two inverted sub-basins that are now the Bilas and Bishri blocks. TheEuphrates Fault System and Abd el Aziz-Sinjar grabens in eastern Syria are largeextensional features with a more recent history of Neogene compression and partialinversion. The Dead Sea transform plate boundary cuts through western Syria and hasassociated pull-apart basins.
The geological history of Syria has been reconstructed by combining the interpretedgeologic history of these zones with tectonic and lithostratigraphic analyses from theremainder of the country. Specific deformation episodes were penecontemporaneouswith regional-scale plate-tectonic events. Following a relatively quiescent early Paleozoicshelf environment, the NE-trending Palmyride/Sinjar Trough formed across central Syriain response to regional compression followed by Permian-Triassic opening of theNeo-Tethys Ocean and the eastern Mediterranean. This continued with carbonatedeposition in the Mesozoic. Late Cretaceous tectonism was dominated by extension inthe Euphrates Fault System and Abd el Aziz-Sinjar Graben in eastern Syria associatedwith the closing of the Neo-Tethys. Repeated collisions along the northern Arabian marginfrom the Late Cretaceous to the Late Miocene caused platform-wide compression. Thisled to the structural inversion and horizontal shortening of the Palmyride Trough andAbd el Aziz-Sinjar Graben.
INTRODUCTION
Since the late 1980s, the goal of the Cornell Syria Project has been to analyze and map the tectonichistory of the structurally deformed areas of Syria. Understanding this rich history can yield a fullerappreciation of the plate-tectonic processes in the eastern Mediterranean region. It can also provide abetter understanding of the likely occurrence and distribution of natural resources. Although notcomparable with the vast hydrocarbon reserves of the Arabian Gulf, the resources of Syria arenonetheless economically important, and there is potential for further significant discoveries.
Much previous work has concentrated on relatively distinct structural provinces within Syria. Thegoal of this paper was to synthesize the tectonic evolution of the entire country by integrating ourprevious interpretations with new regional structural maps, and incorporating significant additionallithostratigraphic knowledge. After outlining the tectonic setting of the area, we provide a briefsummary of previous work. Our regional mapping is then discussed, including a database descriptionand presentation of new lithostratigraphic interpretations, structural maps, and a new tectonic map ofSyria. The result is a Phanerozoic geologic and tectonic model for Syria in a plate-tectonic framework.We conclude by discussing the hydrocarbon habitats in Syria, and their relationship to the tectonicevolution of the region.
Brew et al.
574
GEOLOGICAL REVIEW
Tectonic Setting
Syria is close to the leading edge of a continent/continent collision where the Arabian Plate is convergingon Eurasia at 18 2 mm/year in a roughly north-northwesterly direction (McClusky et al., 2000). Thiscollision is manifest in the active transform and convergent plate boundaries that are currently proximalto Syria (Figure 1), and have been so for most of the Phanerozoic. The events on these boundaries (andtheir ancient counterparts) have largely controlled the Paleozoic, and particularly Mesozoic-Cenozoic,tectonics of Syria.
The most prominent plate margin at the present-day is the Zagros fold and thrust belt (Figure 1) thattrends northwesterly through western Iran and eastern Iraq. It accommodates the convergence ofArabia with Eurasia by widespread thrusting, folding, and significant crustal shortening. Along the
N
BAHRAIN
Nubian Shield
Arabian Shield
KUWAIT
EGYPT
IRAQ
SYRIA
TURKEY
IRAN
Caspian Sea
CYPRUS
Mediterranean Sea
SAUDI ARABIA
Arabian Gulf
JORDAN
Damascus
Red Sea
0 300
km
QATAR
Palmyride
s
BitlisSuture
East AnatolianFault
North AnatolianFault
LevantineSubplate
Sinai Subplate
AnatolianSubplate
EURASIAN PLATE
ARABIAN PLATE
AFRICANPLATE
Wadi Sirhan
Dead
Sea
Fa
ult S
yste
m
Najd Fault System
Zagros Thrust ZoneZagros Fold Belt
Figure 2
Spreading plate marginMajor thrust faultMajor strike-slip faultCenozoic lava fieldPrecambrian basement
Figure 1: Regional tectonic map of the northern part of the Arabian Plate and adjacent areasshowing the proximity of Syria to several active plate boundaries.
Tectonic and Geologic Evolution, Syria
575
northern Arabian margin, the Zagros belt becomes the Eocene-Miocene Bitlis Suture joining the Eurasianand Arabian plates (Hempton, 1985). To the northwest of the Arabian Plate, the dextral Miocene-Pliocene North Anatolian Fault, and the sinistral East Anatolian Fault accommodate movement on theAnatolian subplate that is escaping westward owing to the Arabian-Eurasian convergence (McCluskyet al., 2000).
Converging with the East Anatolian Fault from the south is the Cenozoic Dead Sea Fault System(Figure 1). This sinistral transform fault accommodates the differential northward motion of the Arabianand African plates (Levantine and Sinai subplates) created by the opening of the Red Sea. Theextensional Red Sea and Gulf of Aden plate boundaries form the southwestern and southern boundariesof the Arabian Plate.
Previous Geologic Studies of Syria
At a gross scale, Syria can be divided spatially (Figure 2) into four major tectonic zones and interveningstructural highs (Barazangi et al., 1993). These zonesthe Palmyride area, the Abd el Aziz-Sinjar area,the Euphrates Fault System, and the Dead Sea Fault Systemhave accommodated most of tectonicdeformation in Syria throughout the Phanerozoic, whereas the intervening stable areas remainedstructurally high and relatively undeformed. The style of structural reactivation is dependent on theorientation of the tectonic zones to the prevailing stress pattern.
Figure 2: Topography of Syria, tectonic zones, and location of various text figures. Shaded reliefimage of topography illuminated from the west.
Bishri Block
km
0 100
Figure 5
Figure 6
Figure 3
Figure 4
Med
iterra
nean
Sea
IRAQ
Aleppo Plateau
LEBANON
Al DawwBasin
Mardin HighTURKEY
EUPHRATES FAULT SYSTEM
DerroHigh
Rawdah High
Anah Graben
Kurd DaghMountains
GhabBasin
Rutbah Uplift
Coas
tal R
ange
s
Homs
Depre
ssion Bilas Block
PALM
YRIDE
S
SW Pa
lmyride
s
Damascus
Hamad U
plift
MesopotamianForedeep
JORDAN
Aman
ous M
ount
ains
Anti-L
eban
on M
ounta
ins
Euphrates
Graben
ABD EL AZIZ-SINJAR UPLIFT
DEAD
SEA
FAUL
TSY
STEM Figure 7
36E 37 38 39 40 41 42
37N
36
35
34
33N
Brew et al.
576
Neogene
0
1
2
3
4
Jhar Fault, extensive dextral strike-slip feature separating the SW Palmyrides from the Bilas Block
Bilas Block (Upper Cretaceous outcrop)
Abou Rabahfault-bend fold (Upper Cretaceous outcrop)
Paleogene
Triassic evaporite detachment surface,only locally developed
CretaceousUpper Cretaceous strata onlapping anticlineindicating minor LateCretaceous tectonics
Velocity pull-upof imaged horizons
Jurassic and Triassicrepeated sectionOnlapping and thinning
Middle Eocene strata shows Cenozoic structural uplift
Two-w
ay
Tim
e (s
ec)
Paleozoic
Palmyride AreaThe area loosely referred to as the Palmyrides, can be further divided into the SW Palmyrides, andthe Bilas and Bishri blocks of the NE Palmyrides (Figure 2). During most of the Phanerozoic thePalmyride zone was a sedimentary depocenter (the Palmyride/Sinjar Trough). Seismic reflectiondata (Chaimov et al., 1992, 1993) and drilling records show the SW Palmyrides to have been controlledby NW-dipping late Paleozoic and Mesozoic listric normal faults that were structurally inverted in theNeogene. Unfortunately, poor seismic reflectivity of the older section precludes precise documentationof Paleozoic tectonics.
A significant part of the thickening in the Palmyride Trough can be related to broad subsidence ratherthan extensional faulting (Chaimov et al., 1992), particularly during the Triassic. In the Jurassic andLate Cretaceous, however, normal faulting dominated according to Best (1991), Chaimov et al. (1993),and Litak et al. (1997). Since the Late Cretaceous, the Palmyrides have been subjected to episodiccompression leading to folding and the currently observed topographic uplift.
The SW Palmyrides are dominated by a series of short, SE-verging folds controlled by reverse faults.The short-wavelength anticlines have steeply dipping (in some case overturned) forelimbs, and moreshallowly dipping backlimbs, and are progressively steeper toward the southwest. Chaimov et al.(1993) argued that these folds were the result of fault-propagation folding above inverted normalfaults, linked by sinistral transfer faults. This is supported by well data and outcrop evidence whereTriassic strata are thrust over Santonian rocks (Mouty and Al-Maleh, 1983). Reverse faults withsignificantly decreasing fault dip in the shallow section could reconcile the tight fold axes with therelatively low-angle faults seen at the surface.
Chaimov et al. (1992) mapped a locally developed Triassic detachment level that accommodated somefault-bend fold formation, especially in the northern part of the SW Palmyrides (Figure 3). However,on a regional scale, Chaimov et al. (1993) documented similarly deformed Upper Cretaceous andlower Paleozoic strata, thus arguing against a regional-scale Mesozoic detachment in the SW Palmyrides.
Figure 3: Perspective block model of the Abou Rabah anticlinal structure in the northern part of theSW Palmyrides (see Figure 2 for location). Surface is Thematic Mapper imagery draped overtopography. Faces shown are seismic lines CH-36 (dip line) and CH-45. Image is 31x32 km withapproximately no vertical exaggeration.
Tectonic and Geologic Evolution, Syria
577
In contrast, in the central and northern Palmyrides, Searle (1994) mapped complex folding often in theform of box folds above an Upper Triassic detachment, but only minor reverse faulting. Hence, weinterpret strong along-strike structural variations in the Palmyrides, with thrust faulting becomingless influential toward the northeast. This would agree with the cross-sections of Chaimov et al.(1990) that showed total shortening decreasing from around 20 km in the SW Palmyrides to almostzero in the far northeast.
The extensive low-relief Al-Daww Basin (Figure 2) lies between the SW Palmyrides and the BilasBlock. Dated as a Miocene to Recent depocenter, this intermontane basin contains more than 2,000 mof Cenozoic strata (Chaimov et al., 1992). To the north of the Basin, the Jhar Fault separates the SWPalmyrides from the NE Palmyrides. The Fault has been traced for nearly 200 km in a ENE-directionand shows an average of 1,000 m of uplift on its northern side and significant, but undetermined,amounts of dextral strike-slip (Al-Saad et al., 1992). Well data indicate this was an active extensionalfault at least since the Jurassic. The structural inversion along the Jhar Fault controls the southernedge uplift of the Bilas Block (Figure 2). Deformation within the Block is dominated by strike-slipduplexing where large, relatively undeformed anticlines are bound by steep faults that show verylittle shortening (Chaimov et al., 1990). Along the northern margin of the Palmyrides is the HomsDepression (Figure 2). This large basin shows little or no sign of the structural inversion so prominentin the adjacent Palmyrides, which perhaps suggests a significant fault-controlled detachment of thedepression from the uplifted Bilas Block.
To the north and east of the Bilas Block, the prominent right-lateral Bishri Fault separates the Bilas andBishri blocks. Similar to the Jhar Fault, the transpressional Bishri Fault accommodates uplift of oneblock relative to the other. NE-striking Mesozoic normal faults were more active in the Bishri Blockthan in other parts of the Palmyrides, particularly in Jurassic and Late Cretaceous times (Figure 4).Cenozoic structural inversion of these faults is controlling the present-day NE-plunging anticlinalmorphology of the blocks (McBride et al., 1990; Best, 1991).
Abd el Aziz-Sinjar AreaDuring the late Paleozoic to Late Cretaceous, the Sinjar (Figure 2) and surrounding areas were thenortheastern part of the Palmyride/Sinjar Trough. As in the Palmyrides, accommodation space forlate Paleozoic and Mesozoic clastic sediments several kilometers thick was created largely throughbroad subsidence, although some contemporaneous NE-striking normal faults have been identified(Brew et al., 1999).
Other than this broad trough formation, no significant extension occurred around the Abd el Aziz andSinjar structures until the formation of a network of E-striking faults in the latest Cretaceous. Thesepredominantly S-dipping normal faults and the resulting half grabens formed in the latest Campanianand Maastrichtian and accommodated up to 1,600 m of synrift calcareous, marly sedimentation(Figure 5). The cessation of the extension, as indicated by the termination of faulting, came abruptly atthe end of the Cretaceous.
The currently observed topographic highs (the Abd el Aziz and Sinjar uplifts, Figure 2) are the resultof Cenozoic structural inversion that has been most active in the Late Pliocene to Holocene (Kent andHickman, 1997; Brew et al., 1999). Specifically, the Late Cretaceous E-striking normal faults are beingreactivated in a reverse sense creating fault-propagation folds (Figure 5). Based on limited data, similarand contemporaneous deformation apparently affected the Mesopotamian Foredeep in the extremenortheast of Syria (Figure 2).
Euphrates Fault SystemThe Euphrates Graben (Figure 2) is a fault-bounded failed rift studied extensively by Litak et al. (1998)and de Ruiter et al. (1994). Litak et al. (1997) showed that the Euphrates Fault System is a related butless-deformed zone of extension that extends from the Iraqi border in the southeast to the Turkishborder in the northwest and includes the Euphrates Graben. The lack of widespread inversion limitsthe topographic expression of the Euphrates Fault System (Figure 2).
Brew et al.
578
Faul
t pro
gatio
n fo
lds
on n
orm
al f
aults
reac
tivat
edin
a re
vers
e se
nse
North
east
Sout
hwes
t
Surfa
ce fa
ults
m
app
ed h
ere
Lith
olog
y ch
ange
s fro
mm
arls
to m
ore
resi
stan
tsa
nds
tone
and
limes
tone
s
Eros
iona
l dep
ress
ion
(see F
igure
15)
0 1 2 3 4 5
No
deta
chm
ent s
urfa
ce h
ere
in c
ontra
st to
nor
ther
n SW
Pal
myr
ides
(Figu
re 3)
Bish
ri Bl
ock
sout
hern
bo
undi
ng fa
ults
: nor
mal
faul
ting
in M
esoz
oic,
reve
rse
in C
enoz
oic
Clos
e to
sou
ther
n lim
it of
Pa
lmyr
ide
defo
rmat
ion
1 2 3
Two-way Time (sec)900
800
700
600
500
400
Topography (m.a.s.l.)
010
km
Approximate vertical scale (km)
Neo
gene
Pale
ogen
e
Pale
ozoi
cM
. and
L. T
riass
ic
Uppe
r Tria
ssic
Low
er C
reta
ceou
s
Uppe
rmos
tCr
etac
eous
Pale
ozoi
c
Uppe
r Cre
tace
ous
Jura
ssic
Naje
eb
Al H
yr
Bis
hri
0
Bish
ri Bl
ock:
st
ruct
ural
ly in
verte
d ba
sin
with
thic
kene
d Tr
iass
ic to
Up
per C
reta
ceou
s st
rata
Figu
re 4
: In
terp
reta
tion
of
mig
rate
d s
eism
ic p
rofi
le A
LA
N-9
0-10
fro
m S
W e
dge
of
Bis
hri
Blo
ck in
the
NE
Pal
myr
ides
(see
Fig
ure
2 f
or lo
cati
on).
Das
hed
inte
rpre
tati
on is
sp
ecu
lati
ve b
ecau
se o
f p
oor
dat
a.
Tectonic and Geologic Evolution, Syria
579
A Turonian-Coniacian age unconformityprobably marking prerift upliftis extensively developedin the Euphrates Graben, and the underlying limestone is eroded and dolomitized. Overlying redbedsgrade into progressively deeper water carbonate facies (Litak et al., 1998). Senonian rifting that resultedin about 6 km of extension and an undetermined amount of strike-slip movement was accommodatedby a distributed system of steep normal faults. The synrift carbonate deposition culminated in theCampanian to early Maastrichtian with the deposition of up to 2,300 m of deep-water marly limestoneswithin the graben (Figure 6). Rift-related extension stopped during the Maastrichtian.
The Paleogene was marked by widespread thermal subsidence as the lithosphere reestablished thermalequilibrium after rifting (Litak et al., 1998). The Euphrates Fault System experienced minor dextraltranspression and reactivation during the Neogene. Compressional features are best developed in thenorthwest of the fault zone where reverse and strike-slip movement and some associated minor fault-propagation folding occurred on reactivated Late Cretaceous normal faults. To the south and west ofthe Euphrates Graben is the Rutbah Uplift. The term Hamad Uplift has been used by Mouty andAl-Maleh (1983) to describe the NE-trending paleogeographic high on the northern margin of theRutbah Uplift in Syria (Figure 2).
Dead Sea Fault SystemThe Dead Sea Fault System is a major sinistral transform plate boundary separating Africa (Levantinesubplate) from Arabia, and accommodating their differential movement. Total offset on the southernportion of the fault is well established to be around 105 km (Quennell, 1984). Some authors havesuggested two episodes of strike-slip motion on the Dead Sea Fault System in concert with a two-phase Red Sea openingMiocene slip of 60 to 65 km, and post-Miocene slip of 40 to 45 km (Freundet al., 1970; Quennell, 1984). Other authors (e.g., Steckler and ten Brink, 1986) have advocated a moreconstant Red Sea extension.
Along the northern segment of the fault (from Lebanon northward) the age and rates of faulting areunclear due to a lack of piercing points, although total post-Miocene offset has been reported as lessthan 25 km (Trifonov et al., 1991). These observations and work in the Palmyrides have been combined
0 5
km
Lower Cretaceous and Upper Triassic
NeogenePaleogene
0
54
123
Appr
oxim
ate
dept
h (km
)
Limits of MiddleMiocene outcrop
Strike-slipfaulting
Jebel Abd el Azizelevation 932 m Cretaceous
outcrop Surfacefaulting
Average elevation north of Jebel Abdel Aziz is ~300 m
Two
-wa
y Ti
me
(sec
)
0
1
2
Middle Cambrianand older
Lower Paleozoic
Middle and Lower TriassicUpper
Cretaceous
Shiranish(synrift)formation
Maghlouja
Figure 5: Perspective block model of the Abd el Aziz uplift in NE Syria (see Figure 2 for location).Surface is Thematic Mapper imagery draped over topography. Faces shown are seismic linesUN-350 (dip) and SY-48N. Image 29x41 km: topographic exaggeration about x 5; subsurfaceexaggeration about x 2.
Brew et al.
580
into a model in which the northern part of the Dead Sea Fault System has been active only during thesecond (post-Miocene) phase of faulting. In this model, 20 to 25 km of post-Miocene sinistral motionhas been accommodated along the northern fault segment, and another 20 km in the shortening of theadjacent Palmyride fold and thrust belt (Chaimov et al., 1990), thus accommodating the full 40 to 45km of post-Miocene slip.
The northern segment of the Dead Sea Fault System strikes parallel to the coast through western Syria,and is clearly defined both topographically and structurally (Figure 2). Along the fault in westernSyria is the Ghab Basin (Figure 7), a deep Pliocene to Holocene pull-apart structure (Brew et al., 2001).The Ghab Basin opened in response to a left-step in the fault, although sinistral motion fails to be fullytransferred across the basin, resulting in the horse-tailing of the fault system observed northwardinto Turkey.
The Syrian Coastal Ranges, in places more than 1,500 m high, occupy most of the Syrian onshore areawest of the Dead Sea Fault and Ghab Basin (Figure 2). An extensive karst terrain, a gently dipping(about 10) western limb, and a chaotic, steep, eastern limb where Triassic strata are exposed, characterizethe area. Stratigraphic relationships indicate that the uplift of the Coastal Ranges is part of the extensiveSyrian Arc deformation (Late Cretaceous and Tertiary compressional folding along the easternMediterranean coast) that has been documented in the Levant (Walley, 2001). The Coastal Rangeshave clearly been affected by the propagation of the Dead Sea Fault System and formation of the GhabBasin, resulting in the steep eastern limb (Figure 7) and the possible rotation of the block (Brew et al.,2001).
Figure 6: Perspective block model of the Euphrates Graben (see Figure 2 for location). Surface isThematic Mapper imagery draped over topography. Faces shown are seismic lines PS-14 (dip) andPS-11. Image 31x20 km.
Dablan
Qahar
Tayyani
Heavily cultivatedQuaternary fluvialdeposits
Very slight Neogenestructural inversion
Miocenecontinental clastics
Euphrates River
Two-w
ay
Tim
e (se
c)
1
2
0
3
Carboniferousand Silurian
LowerCretaceous
Triassic
Late Cretaceousnormal faults
Upper Ordovician
Lower Ordovicianand older
Appr
oxim
ate
dept
h (km
)
0
1
2
3
4
65
7
Paleogene
Neogene
UpperCretaceous
?
Tectonic and Geologic Evolution, Syria
581
0 1 2 3 4Two-way Time (sec)
Ord
ovici
an a
ndUp
per C
ambr
ian
Dea
d Se
a
Faul
t
Mid
dle
Cam
bria
na
nd
olde
r
Dee
pest
bas
infill
~3,
400
mTD
of w
ell
3,08
5 m
.b.s
.l.
Low
er C
reta
ceou
s,Ju
rass
ic an
dUp
per T
riass
ic
Pale
ogen
e a
ndUp
per
Cret
aceo
us
Mid
dle
and
Low
er T
riass
ic
Hea
vily
kars
tifie
dJu
rass
ic an
d Cr
etac
eous
limes
tone
(dip
~10
W)
Plio
cene
/ Qu
ater
nary
basin
fill
Pull-
apar
tG
hab
Basin
:e
leva
tion
170
m
Coas
tal R
ange
s:m
ax.
ele
vatio
n 1,
562
m
Surfa
ce tr
ace
ofD
ead
Sea
Faul
t Sys
tem
Gha
b
Not
e st
rong
late
ral v
eloc
ityva
riatio
n: v
ertic
al s
cale
varie
s al
ong
prof
ile
Figu
re 7
: Per
spec
tive
blo
ck m
odel
of
the
Coa
stal
Ran
ges/
Gh
ab B
asin
alo
ng
the
lin
e of
the
Dea
d S
ea F
ault
Sys
tem
(see
Fig
ure
2 f
or lo
cati
on).
Su
rfac
e is
Th
emat
ic M
app
er im
ager
y d
rap
ed o
ver t
opog
rap
hy.
Alo
ng-
bas
in s
eism
ic p
rofi
le is
lin
e G
A-6
an
d c
ross
-bas
in p
rofi
le is
GA
-3.
Ima g
e 90
x41
km
: top
ogra
ph
icex
agge
rati
on a
bou
t x 4
.
Brew et al.
582
STRUCTURAL AND STRATIGRAPHIC MAPPING
Database
The database available for this work is extensive by academic research standards, and this is the firsttime that all the data have been considered together. The primary data are 18,000 km of hardcopymigrated seismic reflection profiles of various vintages, and drilling records from over 400 wellsmany with comprehensive suites of logs (Figure 8). Supplemental data include 1,000 km of seismicrefraction, remote sensing and topographic imagery, gravity maps, and 1:200,000-scale geologic maps.
Concerning the interpretation of the seismic reflection profiles, the Cenozoic section is fairly unreflectivewith the exception of some Miocene evaporite layers (the Lower Fars and Dibbane formations). Thecarbonate Mesozoic section contains prominent seismic reflectors, and regional unconformities areeasily distinguished. The clastic Paleozoic section is poorly reflective with the exception of severalabrupt facies changes in Cambrian and Ordovician strata that form regionally observed reflectors.Paleozoic reflectors include the Burj limestone between the clastic Zabuk and Sosink formations, andthe Swab shale between the Khannaser and Affendi sandstones (Figure 9). Data quality decreasesmarkedly in areas of complex structure, most notably in the deeper areas of the Euphrates Graben andmost of the SW Palmyrides. Recordings are also very poor in areas of Cretaceous limestone on the
Figure 8: Locations of seismic reflection surveys and exploration and development wells. Wellcolors indicate depth of penetration; symbols show best available knowledge of the status ofwells summarized from various literature sources.
Seismic reflection profiles
TURKEY
IRAQ
JORDAN
LEBANON
Gas showOil showGas wellOil wellDry well
SYRIA
36E 37 38 39 40 41 42
36E 37 38 39 40 41 42
km
0 100
Med
iterra
nean
Sea
Blue wells haveMesozoic terminations
Green wells haveCenozoic terminations
Red wells havePaleozoic terminations
N
37N
36
35
34
33
37
36
35
34
33
Tectonic and Geologic Evolution, Syria
583
Bilas Block, and basaltic outcrops (Wadi Sirhan traps) in southwestern Syria. Because the metamorphicbasement does not form a clear event on reflection records, high-quality, multifold refraction datahave been used to determine the depth to basement throughout Syria (Seber et al., 1993; Brew et al.,1997). Well-to-seismic ties are based on synthetic seismograms and associated time-depth curves.
The locations of our data, including all digitally held data, are stored within a Geographical InformationSystem (GIS) for easy retrieval and analysis. Many data interpretations have been conducted withinthe GIS, thus harnessing the power of multiple-dataset visualization, manipulation, and combination(for more details see Brew et al., 2000). As the limitations of a printed journal do not allow a fullappreciation of this digital approach, we have provided downloadable versions of many of our resultsand interpretations via the Internet (http://atlas.geo.cornell.edu/syria/welcome.html).
Lithostratigraphic Evolution
Recent contributions to the understanding of Syrian stratigraphy and paleogeographic evolution arerelatively numerous (e.g., Ponikarov, 1966; Al-Maleh, 1976, 1982; Mouty and Al-Maleh, 1983, 1988,1992, 1994; Sawaf et al., 1993; Mouty, 1998). These workers have concentrated on the extremely well-exposed Mesozoic carbonate section in the Palmyride fold and thrust belt, the Syrian Coastal Ranges,and the Kurd Dagh Mountains (Figure 2). Most recently, Sharland et al. (2001) have provided the firstsequence stratigraphic synthesis of Arabian Plate stratigraphy.
Using extensive drilling records, surface observations, and preexisting studies, we present a newgeneralized lithostratigraphic chart showing the variations of Syrian strata in time and space(Figure 9). The dating of the drilling records was accomplished using the biostratigraphic techniquesof the Syrian Petroleum Company. Clearly illustrated in Figure 9 is the shift from predominantlyclastic Paleozoic deposition to Mesozoic and Cenozoic carbonates. Furthermore, numerous widespreadunconformities showing long-lived hiatuses and erosion occur throughout the section, particularlyduring the Devonian and Late Jurassic. Many of the unconformities that we recognize in Syria arepenecontemporaneous with the boundaries of Arabian Plate (AP) tectonstratigraphic megasequencesof Sharland et al. (2001), denoted AP 1 to 11. These correlations are noted in the text and on Figure 9.Throughout this work we have used the timescale of Gradstein and Ogg (1996), consistent with Sharlandet al. (2001).
Figure 10 is a series of isopach maps of the four major Mesozoic and Cenozoic sedimentary packages,as derived from well and seismic data. The long-lived Rutbah-Rawda Uplift and Aleppo Plateau(Figure 2) show the least complete stratigraphic sections whereas the section is most complete in theprominent Palmyride/Bishri/Sinjar depocenter. For much of the early Mesozoic, the Palmyridedeposition was linked to the Sinjar area (Figures 10a and 10b), whereas for the Late Cretaceous, Sinjarstrata show much closer affinity to rocks of similar age in the Euphrates Graben. This reflects the shiftin subsidence from the Palmyride/Sinjar Trough to the Late Cretaceous fault-bounded extension ineastern Syria (Figure 10c). Furthermore, note the limited Jurassic/Lower Cretaceous section causedby widespread erosion and non-deposition related to regional Late Jurassic/Early Cretaceous uplift.Preserved Cenozoic patterns are dominated by subsidence along the Euphrates Fault System (Figure 10d).
The various formation names used in Syria are often site-specific (Figure 9), leading to a cluttered andconfusing nomenclature. Furthermore, surface and subsurface geologists have historically useddifferent nomenclatures, so compounding the already difficult task of correlating subsurface and surfaceformations. Paleozoic formations in particular are notoriously difficult to distinguish because ofscattered drilling penetrations that compound the often poor differentiation in drill logs, thus renderingdetailed chronology impossible (e.g. Ravn et al., 1994). In rocks of Mesozoic age, confusion involvingthe Kurrachine through Serjelu formations is well-known as they have distinctly different ages inSyria compared to the similarly named formations in IraqMiddle Triassic to Upper Triassic in Syria,versus Upper Triassic to Middle Jurassic in Iraq (see Sharland et al., 2001). In our discussion of Triassicand Jurassic strata we have used traditional formation names (as maintained by the Syrian PetroleumCompany and widely used in the literature) and their modern (e.g. Mulussa Group) equivalents. Thedetailed correlation of Syrian formations, and integration into the regional scheme of Sharland et al.(2001) is of pressing importance.
Brew et al.
584
Figu
re 9
: Gen
eral
ized
lith
ostr
atig
rap
hy
of S
yria
bas
ed o
n s
urf
ace
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rvat
ion
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ing
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rds.
Tim
e in
terv
als
not
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cale
; rel
ativ
ed
ates
of A
rab
ian
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te (A
P) t
ecto
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aseq
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ies
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own
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efer
ence
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ed a
rrow
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dic
ate
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r h
oriz
ons
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ped
in F
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re 1
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ed d
ots
and
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mb
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esp
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me
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nts
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Fig
ure
16.
Not
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rmat
ion
nam
es in
low
er M
esoz
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of E
up
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tes
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?
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er
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Upp
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s / S
tage
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iddl
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PALEOGENENEOGENE
Mio
cene
Plio
cene
Qua
tern
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PER
MIA
N
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ONI
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Long
-term
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(Haq
et al
.,19
88)
12345689 7101112A
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0
AP5AP9
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Coas
tal
Ran
ges
Ale
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Plat
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ides
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Palm
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0
Arab
ian
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ces
(Sha
rland
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Tectonic and Geologic Evolution, Syria
585
The main trends of Phanerozoic thickness changes in Syria (Figure 11) include a southward and eastwardthickening of early Paleozoic strata (illustrated by the East Ratka-101 well), on the Gondwana passivemargin. In the late Paleozoic and Mesozoic, deposition shifted to the west (Abou Zounar section) asthe Levantine passive margin developed (Best et al., 1993). From the late Paleozoic onward, the influenceof the long-lived structural highs of the Rutbah-Rawda Uplift (Tanf-1 well) and Aleppo Plateau(Khanasser-1 well) is apparent. Late Paleozoic and Mesozoic strata are concentrated in the Palmyride/Sinjar Trough, with significant along-strike variation apparent (Bishri-1 and Derro-2 wells). Rapidthickness changes in eastern Syria are associated with Late Cretaceous basin formation (Ishara-101well, Euphrates Graben; Tichreen-301 well, Sinjar Graben), and the influence of Neogene MesopotamianForedeep formation (Swedieh-110 well). Finally, evidence of the uplift and erosion of the Cenozoicsection is seen in the Palmyrides (Balaas-1 well and Abou Zounar section) and Sinjar Uplift(Tichreen-301 well).
Subsurface Structural Maps
We present new subsurface structural maps of four horizons chosen for their geophysical prominenceand tectonic significance (Figures 12a to 12d; stratigraphic positions shown in Figure 9). Each mapshows the present depth to the top of the subject horizon, together with the overlying subcroppingformation, and the current structure.
Areas of highest data density in Syria are invariably those where hydrocarbon production is highest,or where the structure is most complex. Accordingly, these maps show most structure on the EuphratesFault System, parts of the Palmyrides, and in northeastern Syria. However, as data quality and densitydecrease with depth, so does the accuracy of these maps. For example, 460 wells penetrate the topCretaceous horizon whereas only 190 reach as deep as the Paleozoic (Figure 8). The degree of reliabilityin the subsurface mapping of the lower Mesozoic and Paleozoic of the Palmyride region is the lowest,as seismic data are generally not interpretable and well penetrations are few.
In eastern Syria in particularly, the structural mapping was at a much larger scale (typically 1:500,000)than presented in this paper. As a result, there are countless small structures beyond the presentationresolution; conversely, in areas of very low data density, some large faults undoubtedly remainunmapped. The chosen scale of presentation is a compromise.
The maps are not structurally restored. They show present deformation rather than the structure anddepths at the time of deposition of the target horizon. This is why, for example, the Top Triassichorizon demonstrates reverse faulting in the SW Palmyrides although at the time of deposition thesewere normal faults. The symbols on the faults are designed to show the approximate past history offault movement. In addition, present-day depths are shown not those during deposition. For example,the top Paleozoic in the Palmyrides is shown as predominantly uplifted (Figure 12d), whereas it wasa depositional topographic low.
Top Cretaceous
The Top Cretaceous horizon (Figure 12a) illustrates well the effects of Syrian Cenozoic compressionaltectonics. Note the strongly inverted Palmyride Trough (especially the Bilas Block), and the Abd elAziz-Sinjar Uplift. The large sag above the Euphrates Graben is a result of the Paleogene thermalsubsidence. Recent basin formation in western Syria is also illustrated. In general, faulting in easternSyria halted before the end of the Cretaceous. Hence, unless there has been Cenozoic reactivation andfault-propagation of these features, the faulting is not observed at the Top Cretaceous level. The well-developed Al-Daww Basin in the central Palmyrides affected all stratigraphic levels.
Top Lower Cretaceous
The Lower Cretaceous sandstone is a good seismic reflector and forms many hydrocarbon reservoirsin Syria (Figure 12b). Hence it is of particular economic interest. As shown by the subcrop distribution,this sandstone was deposited across most of Syria except on the exposed Rutbah-Rawda Uplift from
Brew et al.
586
37E
37N
N0
km
100
(a)
Thickness (m)
IsopachFault
1,5002,0001,0001,5005001,0000500
2,5003,0003,000+
Outcrop
2,0002,500
(b) 37E37N
Cenozoic
Upper Cretaceous
Tectonic and Geologic Evolution, Syria
587
37E
37N
N0
km
100
(c)
(d) 37E37N
Triassic
Lower Cretaceous and Jurassic
Figure 10: Isopach maps of Syriashowing the present thickness ofthe four major Cenozoic andMesozoic sedimentary packages, asderived from well and seismic data;contours at 250 m intervals; coloredunits 500 m thick: (a) Cenozoic, (b)Upper Cretaceous, (c) LowerCretaceous and Jurassic, (d) Triassic.
Brew et al.
588
Figu
re 1
1: 3
-D f
ence
dia
gram
gen
eral
izin
g p
rese
nt s
edim
enta
ry th
ick
nes
s va
riat
ion
s th
rou
ghou
t Syr
ia.
Not
e th
at th
e d
iagr
am is
vie
wed
fro
m th
e N
W.
Neog
ene
Pale
ogen
eJu
rass
icTr
iass
icUp
per P
aleo
zoic
Lowe
r Pal
eozo
icCr
etac
eous
Swed
ieh-
1100
5,76
6m
Buss
ra-1
3,93
3m
Fidi
o-1
4,11
2m
Tan
f-13,
376m
Baflio
un-1
2,64
1m
Tich
reen
-301
4,12
1m
Enay
at-1
2,53
2mIs
hara
-101
3,61
9m
Khan
asse
r-14,
121m
Der
ro-2
3,19
8mBi
shri-
14,
308m
Bala
as-1
3,19
8m
Abou
Zou
nar
(base
d on
surfa
ce s
ectio
n)
East
Rat
ka-1
013,
100m
SYRI
A
N
Baflio
un-1
Buss
ra-1
Swed
ieh-
1100
Tectonic and Geologic Evolution, Syria
589
which these sands were largely derived (de Ruiter et al., 1994). Later, they were eroded from exposedparts of eastern Syria.
The map shows the full extent of the Euphrates Fault System and Abd el Aziz-Sinjar deformation.Note the distribution of normal faulting in the Euphrates Graben with no major rift-bounding faults.In northeastern Syria, the superposition of the three prominent fault directions is illustrated. Thismap and those on underlying horizons (Figures 12c and 12d), generally show very similar structures.This is because much of the structure in Syria developed on deeply penetrating, high-angle faults.The net sense of offset of any particular horizon changes down section and this is observed on many ofthe mapped faults. However, the locations of the faults remain essentially fixed at this scale ofpresentation. Although some faults only cut the lower portion of the sedimentary column, they areoften either too small or too poorly imaged to be mapped. The biggest difference between Figures12a to 12d is the depth to top of the chosen horizon. Obviously, this is a function of the thickness ofthe strata above it. As we have seen (Figure 11), this can change considerably throughout Syria.
Top Triassic
The Triassic subcrop distribution (Figure 12c) shows the extensive Mulussa F deposition (uppermostTriassic, Serjelu Formation) that covered much of the country. It marks the beginning of a regionaltransgression that continued through the Early Jurassic. Note that some of the Formation was removedby Late Jurassic/Early Cretaceous erosion especially in eastern Syria; thus the original deposition waseven more extensive. The underlying Mulussa Group shows progressively limited extent up-section,again affected by widespread Late Jurassic/Neocomian erosion after regional deposition(Sharland et al., 2001).
Top Paleozoic
Figure 12d has the poorest accuracy of the four maps presented due to a severe decrease in the qualityof seismic reflection data from Paleozoic depths, and fewer well penetrations. As with the overlyinghorizons, the greatest depths are found in the Sinjar Trough and the Euphrates Graben, and in isolatedbasins of western Syria. Note the broader downwarping at this level in the Sinjar area that indicatesthe broad extent of the Triassic Sinjar Trough.
The subcrop pattern is dominated by the widespread Permian Amanous Formation. The map alsoshows the continuation of the Permian Palmyride Trough into the Sinjar area. Note that in the invertedareas of the Palmyrides and Sinjar uplifts, reverse faults are still shown at this level based on well andseismic data showing uplift across these structures. However, associated fault-propagation folds aregreatly subdued or absent (Chaimov et al., 1993). Furthermore, in the southwest of the Palmyride foldand thrust belt, the Top Paleozoic is below the local Triassic-age detachment, and therefore is notsignificantly faulted or folded. However, in the Bilas and Bishri blocks, the thick-skinned deformationhas affected all structural levels. Again, the quality of the mapping is relatively poor for these structures.
Deeper Crustal Structure
The crystalline Precambrian basement in Syria is generally deep (>6 km) and has not been penetratedby drilling. Furthermore, the basement does not form a good seismic reflector. Hence, we have mappedthe basement (Figure 13) using seismic refraction data (Seber et al., 1993; Brew et al., 1997). The depthto the Moho beneath Syria has been estimated from receiver function analysis (E. Sandvol, personalcommunication, 2000). The limits of Moho depths shown on Figure 13 have been calculated fromaverage crustal velocities in the range of 6.2 to 6.8 km/sec. Using the Bouguer gravity anomaly fieldfor Syria (BEICIP, 1975), plus the additional information for basement and Moho depths, we developednew gravity models along two profiles across the Palmyrides (Figure 14).
The first profile crosses the Aleppo Plateau, SW Palmyrides, and the Rutbah Uplift, and shows aclearly dichotomous gravity anomaly on either side of the Palmyrides (Figure 14a). External controlson Moho and basement depths projected along strike into the section, are shown as boxed annotations.
Brew et al.
590
Normal faultReverse faultStrike-slip faultNet normal with oldernormal and reverse motionNet reverse witholder normal motion AnticlineSyncline
Predominant movement on faultsmany with complex history(Unmarked faults have no distinctive sense of motion)
Abd el Aziz Uplift
SinjarUplift
South
west
Palm
yride
s
Ant
i-Leb
anon
CoastalRanges
Top Cretaceous
5001,000+1,000
0500 0 -500
-500 -1,000 -1,000 -1,500-1,500 -2,000-2,000 -2,500-2,500 -3,000-3,000 -3,500-3,500 -4,000-4,000 -4,500-4,500 -5,000
Depth to Top of Unit (m)(in relation to sea level)
Surface Geology
Euphrates Graben
Upper CretaceousLower CretaceousJurassic
37E
37N
(a)
BilasBlock
BishriBlock
Top Lower Cretaceous 37E37N
(b)
Stippled areas indicateextent of no Lower Cretaceous subcrop
In stippled area, Souknhne Formation is the Top of Cretaceous. In all other areas (except eroded parts) Shiranish Formation is Top of Cretaceous.
Tectonic and Geologic Evolution, Syria
591
Top Triassic37E37N
(c)
Black contours and labels show the limits of the uppermost subcropping Triassic formations
KA = Kurrachine AnhydriteKD = Kurrachine Dolomite
Top Paleozoic37E37N
(d)
1000
km
N
Black contours and labelsshow the limits of the uppermost subcropping Paleozoic formations
No Triassic
Butm
a
Butma
Butma
Butma
Butm
a
Butma
K.A.
K.A.
K.D.
K. Dolomite
Allan/Mus
s
Allan/MussAllan/Muss
Adaya
Allan
/Mus
s
Affendi
Affendi
Affen
di
Tanf
Tanf
TanfTanf
Marka
da
Markada
Markada
Markada
Markada
Mar
kada
Tanf
Tanf
Swab
Aday
a
Adaya
Adaya
Adaya
K. An
hydr
ite
K. Anhydri
te
K. Anhy
drite
K. Do
lomite
K. Dolo
mite
K. Do
lomite
No Tr
iassic
Allan/Muss
Allan/M
uss
Serjelu
Serjelu
Serjelu
Serjelu
Butm
aSe
rjelu
Allan/Mus
s
K. Do
lomite
Aday
a
Amanus
Amanus
Mark
ada
Aman
us
Figure 12: Depth, structure, andstratigraphy of subsurfacegeological horizons as derived fromseismic and well data (see Figures 8and 9): (a) Top Cretaceous, (b) TopLower Cretaceous, (c) Top Triassic,(d) Top Paleozoic.
Brew et al.
592
N
mgal-100
-75
-50
-25
0
25
50
Seismic refraction profile Depth to metamorphic basementfrom refraction interpretationMinimum depths to basementfrom well data
Gravity profile (Figure 14)Seismograph station
Depths are in kilometers below sea level
Probable Moho depth range usingreasonable crustal velocities (seetext) and receiver functionanalysis from seismological data
6.0 2831
2831
4244
3740
2831
>3.1
>3.1
b
a
Rmahintrusives trend
0 100
km
5.5
8.0
5.05.5
10.0
8.5
>7.0
>7.5
8.0
9.0
6.0
6.0
5.5
>5.3
Using these constraints, we constructed a suitable density model beneath the profile with less thanabout 3 mgal difference between observed and calculated gravity responses. Firstly, we investigatedcrustal-scale effects without concern for the second-order anomalies. The result (black line inFigure 14a) shows a large difference in crustal thickness and density on either side of the Palmyrides,with a discontinuity around the present surface position of the Jhar Fault. A small crustal root, of 2 to3 km, is required beneath the SW Palmyrides to satisfy the receiver-function Moho depth. Speculativemodeling of the second-order anomalies along this transect (dashed pink model and anomaly inFigure 14a) shows that arbitrary, high-density intrusions beneath the Palmyrides can be used to matchthe observed anomalies very closely. These intrusions could perhaps be an extension of the Rmahtrend clearly imaged by the gravity data (Figure 13), and described by Best et al. (1990).
The second gravity profile also crosses the Aleppo and Rutbah highs, but traverses the Bilas Block ofthe Palmyrides (Figure 14b). Large density and thickness differences on either side of an interface ator near the Jhar Fault are again required. There is no requirement for a well-developed crustal root,but a small flexing of the southern block on the southern margin of the Palmyrides improves the fit ofthe model.
Figure 13: Bouguer anomaly map of Syria (BEICP, 1975) together with topographic imagery. Note(1) abrupt along-strike variation in gravity anomalies in the Palmyrides coincident with topographicchange, and (2) contrast between Bouguer anomalies north and south of the Palmyrides.
Tectonic and Geologic Evolution, Syria
593
Figure 14: Gravity models on profiles through central Syria (see Figure 13 for locations). Densitiesin g/cm3 in parentheses; boxed comments are constraints other than through gravity modeling;white dots show locations of seismic refraction constraints. (a) Aleppo Plateau, SW Palmyrides,and Rutbah Uplift; anomaly shown with and without two otherwise unconstrained intrusive bodies(striped) that account for second-order gravity anomalies. (b) Bilas Block: note that model does notrequire a significant crustal root beneath the Block.
Distance (km)0 100 200 300
Dep
th (k
m)D
epth
(km)
40
35
30
25
20
15
10
5
0G
ravit
y (m
gals)
-60
-40
-20
0
Gra
vity
(mga
ls)
-60
-40
-20
0
North-northwest South-southeast
North-northwest South-southeast
0 100 200 30045
40
35
30
25
20
15
10
5
0
(b)
With stripedintrusions
Observed
Calculated
Observed
Calculated
(2.99)
Bilas Block
AleppoPlateau
RutbahUplift
RutbahUplift
AleppoPlateau SW Palmyrides
(a)
Seismic-refractionderived basement
Receiver-functionderived Moho
(2831 km)
Receiver-functionderived Moho
(4244 km)
Intrusionalso interpreted
on magnetic data
LOWER CRUST (2.92)LOWER CRUST (2.87)
UPPER CRUST (2.70)UPPER CRUST (2.75)
CENOZOIC (2.30)
MANTLE (3.20)
JharFault?
PALEOZOIC (2.60)
INTRUSION(2.98)
INTRUSION(2.99)
Receiver-functionderived Moho
(3740 km)
LOWER CRUST (2.92)LOWER CRUST (2.87)
UPPER CRUST (2.70)UPPER CRUST (2.75)
CENOZOIC (2.30)
MANTLE (3.20)
Receiver-functionderived Moho
(2831 km)
JharFault?
PALEOZOIC (2.60)
Seismic-refractionderived basement Minimumbasement
depth
Minimumbasement
depth
MESOZOIC (2.40)
MESOZOIC (2.40)
Brew et al.
594
These results support the hypothesis that Syria, like the rest of the Arabian Plate, formed through aProterozoic amalgamation of microplates and island arcsthe Pan-African system (Stoeser and Camp,1985). This left a series of suture/shear zones underlying the continent that have acted as zones ofweakness throughout the Phanerozoic. The difference in basement depth, and crustal thickness anddensity on either side of the Palmyrides could indicate that northern and southern Syria are differentcrustal blocks, sutured along the Palmyride trend. Furthermore, the Jhar Fault, one of the majorstructural features of the Palmyride area, could be marking the position of the suture as first suggestedby Best et al. (1990). Assuming this scenario, crust of Rutbah-Rawda Uplift affinity underlies thepredominantly thin-skinned deformation of the SW Palmyrides, whereas Aleppo Plateau crustunderlies the Bilas and Bishri blocks that exhibit predominantly thick-skinned tectonics. This mightdemonstrate that the Proterozoic architecture of the Arabian Plate is controlling the style, as well asthe location, of Phanerozoic deformation. Walley (1998) argued that this suture zone is traceablewestward through Lebanon. He correlated the deformation style of the northern and southern LebaneseMountains with the NE Palmyrides and SW Palmyrides. Walley (1998) mapped many tens of kilometersof north-south separation between the present locations of his Lebanese and Syrian sutures,presumably suggesting this much translation on the northern part of the Dead Sea Fault System.
The presence of a crustal root appears to follow the leading edge of the southern block. The rootobserved in Figure 14a and the flexure that is observed in Figure 14b could both be interpreted asbending at the leading edge of the southern block. This could be a loading effect created by thePalmyrides themselves preferentially affecting the Rutbah Block, suggesting it may be flexurallyweaker. Alternatively, the increased root formation in the west could be explained by the proximityof profile 14a to the Anti-Lebanon, a crustal load much larger than the Palmyrides.
INTEGRATED TECTONIC MAP
The new tectonic map of Syria (Figure 15: as poster in pocket between p. 596597) shows generaltectonic elements, outcrop distribution, shaded relief imagery, and seismicity. The faults and foldsshown in black were mapped at the surface by Dubertret (1955), Ponikarov (1966), and Searle (1994),or are from our surface observations and limited remote-sensing imagery interpretation. The subsurfacestructure, in red, is modified from the Top Lower Cretaceous structure map (Figure 12b). This levelwas chosen to represent the subsurface as most faulting cuts this horizon, yet it is still relatively closeto the surface. As shown in Figure 12, the sense of motion on these faults may change according to theparticular structural level that is considered.
Figure 15, although relatively accurate at the scale of presentation (1:1,000,000) is undoubtedlyincomplete in some areas. The sense of motion on many of the mapped structures is also ambiguous.In particular, we have mapped many of the reverse faults that core the anticlines of the SW Palmyridesas being reactivated normal faults. Although this is true for many of the faults, some may be thrustfaults detached in the Triassic. Strike-slip activity is also extremely difficult to map accurately in thesubsurface and it is only noted where known with some certainty. Assuredly, many more faults havestrike-slip components than are identified on this map. The map shows again how most deformationin Syria is focused within the four major structural zones of the Palmyrides, the Abd el Aziz-Sinjararea (NE Syria), the Euphrates Fault System, and the Dead Sea Fault System.
Earthquake locations are taken from the International Seismological Center s database(196494), and from the local Syrian seismograph network (199596). Also shown are Harvard CMTfocal mechanisms (197796), supplemented by work at Cornell (Seber et al., 2000). These focalmechanisms are only loosely constrained because of the relatively small size of the events involved.Moreover, the apparent lack of events along the northern Dead Sea Fault System relative to the southernpart of the fault system is a consequence of sparse station distribution in Syria. Nevertheless, there isan obvious concentration of events along the Dead Sea Fault System, some events within the otherSyrian tectonic zones, and very few events in the stable areas of Syria. Also, note the clear alignmentof many events across Syria on the line of the Palmyrides and farther northeast on the trend of thehypothetical suture/shear zone discussed above.
Tectonic and Geologic Evolution, Syria
595
GEOLOGICAL EVOLUTION OF SYRIA
Our regional tectonic and geologic evolutionary model presents the interpreted evolution of Syria andSyrian tectonic zones in a regional and global context (Figure 16: as poster in pocket betweenp. 596597). There are many paleoplate reconstructions for the evolution of the Tethys and easternMediterranean, and the issue is still under debate (e.g. Robertson and Dixon, 1984; Dercourt et al.,1986; Ricou, 1995; Stampfli et al., 2001). The reconstruction shown here (Figure 16) is generalized fromStampfli et al. (2001), and is an aid to discussion, rather than an endorsement of validity. Nevertheless,their model is broadly in agreement with our findings. In the discussions below, we refer to present-day polarities. For example, what we refer to as an early Paleozoic E-facing passive margin, waspredominantly N-facing at that time (Figure 16, frame 1a), but was subsequently rotated approximately90. All the frames in Figure 16 are oriented with north roughly toward the top of the page.
Proterozoic (>545 Ma) to End Cambrian (495 Ma)
It has long been accepted that the southern Arabian Plate formed through Proterozoic accretion ofisland arcs and microplates against northeast Africa, most probably between about 950 Ma and 640Ma (Beydoun, 1991) as part of the Pan-African orogeny. Suture zone relics from this accretion, and theNajd-style faults that formed when these sutures were reactivated are well exposed in the ArabianShield (Stoeser and Camp, 1985). Based on geophysical evidence (see discussion above and Best et al.,1990; Seber et al., 1993; Brew et al., 1997) we suggest that the northern part of the Arabian Plate is aresult of a similar concatenation although with a different orientation. Specifically, we find that thecurrent Palmyride fold and thrust belt may overlie the approximate location of a Proterozoic suture/shear zone. Reactivation of this crustal weakness appears to have profoundly affected the tectonicevolution of Syria throughout the Phanerozoic, from the formation of the Palmyride/Sinjar Trough tothe later Palmyride fold and thrust belt.
From about 620 Ma to 530 Ma, continental rifting and intracontinental extension followed the accretion,together with strike-slip movement on the Najd fault system, and Infracambrian and Early Cambriansynrift deposition (Husseini, 1989) (megasequence AP1 of Sharland et al., 2001). Owing to their greatdepth, no direct dating of the oldest sediments in Syria is available. However, from seismic refractioninterpretation we infer Infracambrian to Lower Cambrian strata between 1 and more than 2.5 kmthick across Syria (Seber et al., 1993; Brew et al., 1997). Significant thicknesses of Infracambrian sandstoneand conglomerate are present in SE Turkey (Derik and Camlipinar formations) and in Jordan (SaramujFormation). Husseini (1989) suggested that these synrift and postrift strata resulted from the JordanValley Rift that formed between Sinai and Turkey during the Infracambrian (Figure 16).
The drilled Cambrian rocks of Syria are arkosic sandstones, probably derived from a granitic basementin the south, together with some siltstone and shale (Figure 16, frame 1a). The exception to the clasticCambrian section is the Early to Middle Cambrian Burj limestone formation that is present throughoutSyria (Figure 9), below the maximum flooding surface (MFS) Cm20 of Sharland et al. (2001). Theregional extent of this monotonously carbonate formation on both sides of the Palmyrides suture ismore evidence for the cessation of cratonization and regional intracontinental extension of northernArabia before the Middle Cambrian (about 515 Ma) as discussed above (Best et al., 1993).
An erosional unconformity at the top of the Cambrian (Figure 9), is just one of many unconformitiesthat punctuate the Paleozoic section. This was a time of relatively shallow water over much of Arabia;consequently, relatively minor eustatic variations easily caused hiatuses and erosion.
Ordovician (495 Ma) to Early Silurian (428 Ma)
Ordovician strata were deposited across a wide epicontinental shelf that was especially well developedon the northern and eastern margins of the Arabian Plate. The Syrian Ordovician section increases inthickness from 1.6 km beneath the Aleppo Plateau to more than 3.5 km in the southeast beneath theRutbah-Rawda Uplift (Figure 11), and in eastern Jordan. Wells in the west of Syria penetrated analmost wholly sandy Ordovician section, whereas those in the southeast intersected significant amounts
Brew et al.
596
of siltstone and shale (Figure 9; Figure 16, frame 1b). These facies and thickness trends in the SyrianOrdovician indicate open-marine conditions to the east, and also in Iraq and Turkey (Sharlandet al., 2001). The source areas for the Ordovician, and other Paleozoic clastics, were the extensiveArabian and Indian Precambrian shields exposed to the south and west (Figure 16, frame 1a), and anever-increasing amount of reworked sediments.
The top Ordovician unconformity is the base of megasequence AP3 of Sharland et al. (2001), whoattribute the unconformity to hinterland uplift in western Saudi Arabia. The Rawda-Rutbah High(Figure 16, frame 2b) in the extreme east of Syria and the western part of Iraq was exposed during thisLate Ordovician to Early Silurian regression. The Upper Ordovician Affendi Formation is missing inthe extreme southeast of Syria, and thinned dramatically over the Rawda High (Best et al., 1993).Beydoun (1991) showed that this exposed/structurally high area extended from Turkey to Saudi Arabiaduring the Late Ordovician and Early Silurian, and probably had a tectonic origin.
Polar glaciation of much of Gondwana, including western Arabia, occurred in the Late Ordovician.Deglaciation in the Early Silurian, as Gondwana drifted towards the tropics, caused sea levels to risesharply flooding much of Arabia and depositing what is now an extremely important regionalhydrocarbon source rock (Beydoun, 1991). In Syria, these Early Silurian graptolitic shales (the TanfFormation, Figure 9), were deposited during this transgression (Figure 16, frame 2b). Although nowthickest within the Palmyride/Sinjar Trough (Best et al., 1993), they were probably originally 500 to1,000 m thick across the entire region.
Late Silurian (428 Ma) to Devonian (354 Ma)
The Lower Silurian section in Syria is directly overlain by Carboniferous clastics, demonstrating anunconformity of major temporal and spatial extent. Strong tectonism and volcanism occurredcontemporaneously at many localities in northern Gondwana. Some authors cite two events. Thefirstloosely referred to as Caledonianis of Late Silurian age and the other is of Middle to LateDevonian/Early Carboniferous age, (Husseini, 1992), referred to as Hercynian sensu lato by Sharlandet al. (2001). The absence of preserved strata in Syria prevents such a distinction there. Suggestions ofthe cause of this tectonism include regional compression caused by the obduction of the Proto-Tethyson what is now Iran (Husseini, 1992); uplift on the flanks of the Paleo-Tethys rifting (Stampfli et al.,2001); or a more localized thermal uplifting event (Kohn et al., 1992) (Figure 16, frame 2a).
Whatever the tectonic cause, strata of Late Silurian and Devonian age are almost totally absent fromArabia, and the underlying Early Silurian shales are substantially eroded. The present subcrop patternof Silurian strata in Syria shows an elongate depocenter roughly along the trend of the currentPalmyrides (Best et al., 1993), and a thinned to absent Silurian succession to the north and south. Thiscould be interpreted as evidence for an Early Silurian initiation of the major Palmyride/Sinjar Trough.However, based on a slight angular unconformity observed at the top of the Silurian (Best et al., 1993),we suggest that this subcrop pattern is a result of Late Silurian and Devonian preferential erosion onthe Rutbah-Rawda and Aleppo structural highs southeast and northwest of the Palmyrides, respectively.
During both the Late Ordovician and Late Silurian/Devonian, the Rutbah and Rawda uplifts wereapparently most prominently exposed east of the current structural and topographic high (compareFigure 2 with Figure 16, frame 2b). These highs were then centered near the present location of theEuphrates Graben. Previous publications (e.g. Litak et al., 1997) have examined the possibility thatthe Euphrates Fault System may have formed above a Proterozoic suture/shear zone similar to thatproposed beneath the Palmyrides. However, given little evidence of subsidence or faulting along theEuphrates trend before Late Cretaceous time, this is now considered unlikely. The Rutbah and Rawdahighs (Figure 2) were evidently connected through most of geologic time until Late Cretaceous dissectionby the Euphrates Fault System. Other than a few episodes of minor subsidence after emergence in theDevonian, the basement-cored Rutbah-Rawda Uplift remained structurally high for the rest of thePhanerozoic. The difference in basement depth across the Euphrates Fault System (Brew et al., 1997)(Figure 13) could be explained by a continuation of the Palmyride suture to the east, combined withthe deep-seated Euphrates faulting.
4.7
4.84.95.1
5.0
5.4
4.8
4.7
6.0
4.8
4.5
5.6
?
?
?
?
/
EuphratesRiver
IRAQ
JORDAN
TURKEY
LEBA
NON
PA
LM
YR
I DE
S
PA
LM
YR
I DE
S
MED
ITER
RAN
EAN
SEA
Ghab BasinUp to 3.4 km of
Pliocene / Quaternaryclastics in pull-apart basin
Northern Dead Sea FaultFormed since Late Miocene,
1,600 m of Late Cretaceous
synextensional strata.Site of older Mesozoic trough
A B D E L A Z I Z / S I N J A RU P L I F T S
SW volcanic fieldsNeogene and Quaternary basalterupted from prominent volcanic
centers aligned NNW
Rutbah UpliftBasement-cored crustal block.
Thick (~7 km) Paleozoicsection, thicker crustthan northern Syria
Coastal Ranges~2.5 km of post-
mid Eocene uplift
Coastal Ranges~2.5 km of post-
mid Eocene uplift
Ghab BasinUp to 3.4 km of
Pliocene / Quaternaryclastics in pull-apart basin
Northern Dead Sea FaultFormed since Late Miocene,
Ear
lyE
arly
Ear
lyE
arly
Late
Late
LM
ML
EM
Late
Ear
lyE
arly
Late
Pale
ogen
eN
eoge
ne/
Quat
erna
ryM
Late
Ear
lyLa
teM
Ear
lyL
Carb
onife
rous
Silu
rian
Dev
onia
nO
rdov
icia
nCa
mbr
ian
Perm
ian
Tria
ssic
Jura
ssic
Cret
aceo
usCE
NOZO
ICPR
E-CA
MBR
IAN
100Ma
200Ma
300Ma
400Ma
500Ma
Ear
lyE
arly
Ear
lyE
arly
Late
Late
LM
ML
EM
Late
Ear
lyE
arly
Late
Pale
ogen
eN
eoge
ne/
Quat
erna
ryM
Late
Ear
lyLa
teM
Ear
lyL
Carb
onife
rous
Silu
rian
Dev
onia
nO
rdov
icia
nCa
mbr
ian
Perm
ian
Tria
ssic
Jura
ssic
Cret
aceo
usCE
NOZO
ICPR
E-CA
MBR
IAN
100Ma
200Ma
300Ma
400Ma
500Ma
AP11
AP10
AP9
AP8
AP7
AP6
AP5
AP4
AP3
AP2
AP1
Terminal collision afternorthern Arabian continental
margin shortening
Post-rift unconformity?
Initial final collisionalong northernArabian margin
Subductionin Neo-Tethys
Paleo-Tethyssuture
Paleo-Tethyssuture
EasternMediterranean
opened
Possible EasternMediterranean
openingPalmyride
trough,aulacogen
Hun superterranesutures to Laurussia
IncipientNeo-Tethysformation
Proto
-Tethy
s sutu
re
Axis
of fu
ture
Paleo
-Tet
hys r
iftin
g
Widespread unconformity
Widespread unconformity
Plate-wide unconformity
Regional 'glacial hiatus'
11a
10a
9a
7a
6a
5a
4a
3a
2a
1a
PLATE RECONSTRUCTION KEY
SYRIA TECTONIC/SEDIMENTATION KEY
Annotations in purple
Syrian Arc
a
b
12b
12b
11b
10b
9b
8b
7b
6b
5b
4b
3b
2b
11b
10b
9b
8b
7b
6b
5b
4b
3b
2b
1b
12a
12a
11a
10a
9a
8a
7a
6a
5a
4a
3a
2a
1a
11a
10a
9a
8a
7a
6a
5a
4a
3a
2a
1a
Bishri Block
IRAQ
Aleppo Plateau
LEBANON
Al DawwBasin
Mardin HighTURKEY
EUPHRATES FAULT SYSTEM
DerroHigh
Rawdah High
Anah Graben
Kurd DaghMountains
GhabBasin
Rutbah Uplift
Coas
tal R
ange
s
Homs
Depre
ssion Bilas Block
PALM
YRIDE
S
SW Pa
lmyride
s
Damascus
Hamad U
plift
MesopotamianForedeep
JORDAN
Aman
ous
Mou
ntai
ns
Anti-L
eban
on M
ounta
ins
EuphratesGraben
ABD EL AZIZ-SINJAR UPLIFT
DEAD
SEA
FAUL
TSY
STEM
km
0 100
Med
iterra
nean
Sea
N
Collision withtrench along
northern Arabianmargin
36
35
34
33
Axis o
f futur
e
Neo-Te
thys ri
fting
Pla
te c
onsu
mpt
ion
ATLA
NT
ICPA
LEO
-TE
TH
YS
Des
truc
tion
For
mat
ion
NE
O-T
ET
HY
SO
cean
spre
adin
gR
iftin
gP
RO
TO-T
ET
HY
SH
un s
uper
terr
ane
dock
s w
ith L
auru
ssia
Spr
eadi
ng b
egin
s in
Nor
th th
en S
outh
Atla
ntic
Sub
duct
ion
begi
ns in
Neo
-Tet
hys
Red Sea forms.Africa-Arabia
separate
Afr
ica-
Eur
asia
con
verg
ePa
ngea
Gon
dwan
a
Terminal Eurasia-Arabia collision
34 Ma
63 Ma
92 Ma
149 Ma
182 Ma
255 Ma
295 Ma
364 Ma
445 Ma
520 Ma
Middle Miocene (15 Ma)
Broad subsidencealong Palmyride / Sinjar
Trough; exact timinguncertain, probablyrelated to regional
folding
Palmyride /Sinjar Troughno longer rifting.
Thermal subsidenceand faulting
Uplift, tilting, volcanism and erosion probably mantle-plume related
Widespread reactivation
of normal faults,especially in NE
Palmyrides.Continued subsidence
Inversion alongLate Cretaceous
faults creates current
topography
Trans-pression,inversion
Extension ceases
Uplift and erosion
Uplift and erosion
Rifting esp.in SE;throw
distributed on many
faults
Continued subsidenceand limited fault
reactivation
Widespreadthermal
subsidence
Minortranspressionparticularly in
NW
Wide-spreadvolca-nism
No
dist
inct
tect
onic
act
ivity
in s
epar
ate
Syr
ian
tect
onic
zon
es;
gen
eral
ly m
arin
e co
nditi
ons
on G
ondw
ana
pass
ive
mar
gin
Uplift and erosion
Widespread transgression
Major rifting stage andsignificant deposition inthe Palmyride / Sinjar
Trough
SouthDSFS
Initial upliftof CoastalRanges?
Gen
eral
ly c
ompr
essi
onal
tect
onic
s an
d em
erge
nce
due
to c
ontin
enta
l con
verg
ence
Red Sea rifting;Arabia moves
N. relative to Africa
Anatolianfaults form
Pan-AfricanProterozoicaccretion
Polar glaciationin west Arabia
Trangression
Regional upliftand
erosion
Rifting, extension,synrift deposition
NajdWrench Fault
System
E-facing passive margin on northern Gondwana
No major tectonic events
Regionalfolding
Neo-Tethys Ocean
spreading alongNorth
Gondwana
Rifting along N. African margin, possibleE. Med.
spreading
Glaciation of
southern Arabia
Ophioliteobduction
Terminalsuturing
Cimmeriaseparates
fromGondwana
Subsidencein East
Mediterranean;development
of passivemargin
Ophioliteemplacement
GEOLOGIC EVENTS INARABIAN PLATFORM
ARABIANPLATE MEGA-
SEQUENCEBOUNDARIES(Sharland et al., 2001)
REGIONALPLATE RECONSTRUCTION
SYRIAN TECTONIC ZONES SYRIASEDIMENTATION AND FACIES TECTONIC AND GEOLOGICEVOLUTION OF SYRIA
FIGURE 16
TOPOGRAPHY AND TECTONIC ZONES OF SYRIA
MajorOceans
MajorContinents
PalmyrideFold and
Thrust Belt
NortheastSyria
EuphratesFault
System
DeadSea FaultSystem(DSFS)
Generalcomments
Latitude of central Arabia ~20o N
Latitude of central Arabia ~24o N
Arabia
Late Eocene (35 Ma)Extensive
volcanism
NEO-TETHYS
LYCIAN
End Cretaceous (65 Ma)
NEO-TETHYS
Late Campanian (75 Ma)
NEO
-TETHYS
Latitude of central Arabia ~8 o N
Santonian (84 Ma)
VARDAR
SEMAIL
NEO-TETHYS
Latitude of central Arabia ~5 o N
Arabia
Aptian (112 Ma)
NEO-TETHYS
ME
LIAT
A
VAR
DA
R
Latitude of central Arabia ~0 o
Arabia
Late Jurassic (156 Ma)
MELIATA
NEO-TETHYS
Latitude of central Arabia ~7 oS
Arabia
Late Triassic (222 Ma)
Apulia
Pelagonia
Cim
merian continent
PALEO-TETHYS
NE
O-T
ET
HY
S
MELIATA
Latitude of central Arabia ~22 oS
Arabia
Late Permian (~249 Ma)
PALEO-TETHYSCim
merian superterrane
Latitude of central Arabia ~25 oS
Late Carboniferous (~295 Ma)
Gondwana
Cimmer
ian sup
erterran
e
PALE
O-TET
HYS
Hun s
upert
erran
e
Latitude of central Arabia ~35 oS
Early Silurian (~435 Ma) Early Silurian (~435 Ma)
Shaly transgressivedeposits
Santonian (84 Ma)
Bishri and Euphratesdepocentersconnected
Minor Syrian Arcdeformation
Accelerated Palmyridesubsidence
RutbahUplift
Aptian (112 Ma)
Marginalmarine
Continued faultreactivation
in Bishri Block
Extensive, marly to marly
limestone deposition
Transtensioncontinues in
Euphrates GrabenUp to 2,000 m
Late Cretaceous synrift deposition
Extension inSinjar / Abd el Aziz,over 1,600 m of fill
AnahGrabenBeginning
of Palmyride uplift,further Syrian arc
deformation
Aafrine Basinforms
Late Permian (~249 Ma)
Slight upliftin SW Palmyrides
Ophioliteemplacement:
affects sedimentationin Aafrin basin
Thermal subsidencebegins above
Euphrates Graben
Northern marginreaches trench:
regional compression
End Cretaceous (65 Ma)
Palmyrides stillgenerally subsiding
Mid Miocene terminal suturing
Palmy
ride tra
nspres
sional
folding
and u
plift
Bishri Blockinversion
No deposition onRutbah and Aleppo uplifts
Dep
ositi
on a
long
subs
idin
g pa
ssiv
e m
argi
n
SinjarTrough
PROT
O-TE
THYS
Latitude of central Arabia ~52 oS
Early Ordovician (~490 Ma)Gondwana
Middle Miocene (15 Ma)Plio-Quaternary
Abd el Azizand Sinjar uplift
Minor Euphrates
transpressionPlio
cene
DS
FS
SirhanGrabenrifting
BishriBlock, some
faulting
Triassicprogressively
onlappingRutbah Uplift
RutbahUplift
Progressively limitedTriassic deposition
Late Triassic (222 Ma)
Evaporitedeposition
Leva
ntin
e m
argi
nde
posi
tion
as
E M
ed. f
orm
s
Extensiv
e postrift
subsiden
ce, some
faulting,e
specially
in SW
Eastwardtransgression
following emergence
Deeper waterfacies in E
Deltaic sandstonessourced in the
S and SW
Main P
almyrid
e /
Sinjar
rifting
episod
e
Over
1,000
m
of Pe
rmo-T
riassi
c
clastic
s
E. Mediterraneanrifting
Rutbah and Aleppopossible uplifted
rift flanks
>1,700
m of
Carbo
niferou
s
clastic
s
Subsidingincipient
Palmyride /Sinjar Trough
HelezAnticlinorium
Extension stopsin eastern Syria
Late Carboniferous (~295 Ma)
Beginning of riftingin Euphrates Graben
Regional uplift, exposureand extensive erosion in
Late Jurassic / EarlyCretaceous, removed mostMid-Upper Jurassic strata
Jurassic thickenswestward
BishriBlock
Continued subsidence,normal fault reactivation
two depocenters inPalmyrides
Late Jurassic (156 Ma)
Regional transgression
Rut
bah
and
Ale
ppo
high
s up
lifte
d sh
ould
ers
of P
alm
yrid
e/S
inja
r tr
ough
Sub
side
nce
and
over
all e
xten
sion
thro
ugho
ut M
esoz
oic,
exc
ept f
orup
lift a
nd m
antle
-plu
me
activ
ity in
Lat
e Ju
rass
ic/ E
arly
Cre
tace
ous
Collision withtrench along
N. margin
LEGEND
Tectonic Features
Dominant Facies inActive Depositional Areas
Approximate Paleogeography
Approximate Generalized Paleogeography
Rift
Approximate plate boundary
SubductionZone
Spreading platemargin
Sandstone
Shale
Limestone
Marlylimestone
Marl
Ophiolite
Dolomiticlimestone
Dolomite
Tectonic Features
PRINTED AUGUST 2001
Reverse fault
Strike-slip fault showingdirection of movement
Normal fault
Relative major depocenter
Volcanic activity
OCEANIC FEATURES IN UPPERCASEContinental features in lowercase
Predominanttransport direction
Syrian international border
Sedimentary trend
Evaporites
DS
FSM
iocene
Late Campanian (75 Ma)Obduction
on northern margin
Mid-Late Eoceneinitial suturing along
northern margin
Late Eocene (35 Ma)Very minorAbd el Azizinversion
Mid-Eocene upliftin Palmyrides
Syrian Arcdeformation, uplift
of LebaneseMountains
Thermal sagabove Sirhan Graben
Broad thermalsubsidence aboveEuphrates Graben
Syrian tectonic evolution as part of the northern Arabian Plate: plate reconstructions are shown in frames 'a' (left); timelines of significant regional and local tectonic events are central; and Syrian tectonic evolution and sedimentation are shown in frames 'b' (right). Plate reconstructions are simplified after Stampfli et al. (2001) and are not to scale relative to each other; present-day Arabia is highlighted. Gradational coloring of timelines indicates degree of certainty. Relative dates of Arabian Plate (AP) tectonostratigrahic megasequence boundaries (Sharland et al., 2001) have been added for reference. Tectonic/sedimentation frames show elements generalized and in the correct contemporaneous position.
Brew, G., M. Barazangi, A.K. Al-Maleh and T. SawafTectonic and Geologic Evolution of Syria.
GeoArabia, v. 6, no. 4, 2001, p. 573-616.
Published by Gulf PetroLinkP.O. Box 20393, Manama, BAHRAINe-mail: geoarabi@batelco.com.bhhttp://www.gulfpetrolink.com
References:
Latitude of central Arabia ~15 o N
Latitude of central Arabia ~13 o N
Arabia
Arabia
Arabia
Arabia
Arabia
EASTERNMEDITERRANEAN
Arabia
36 E 37 38 39 41 42 40
Arabian -NubianShield
37 N
Arabia
Sharland, P.R., R. Archer, D.M. Casey, R.B. Davies, S.H. Hall, A.P. Heward, A.D. Horbury and M.D. Simmons 2001. Arabian Plate sequence stratigraphy. GeoArabia Special Publication 2. Gulf PetroLink, Bahrain, 371 p.
Stampfli, G.M., J. Mosar, P. Favre, A. Pillevuit and J.-C. Vannay 2001. Permian-Triassic evolution of the western Tethyan realm: the NeoTethys/east Mediterranean basin connection. In, W. Cavazza, A.H.F. Robertson and P. Ziegler (Eds.), PeriTethyan rift/wrench basins and passive margins. Memoires du Museum National d'Historie Naturelle, Paris, PeriTethys Memoir 6.
Two-
phas
e S
yria
n A
rc' d
efor
mat
ion
in S
inai
, Lev
ant,
and
Syr
ia
'
EWhalf-grabenformation
Initialuplift
Episodicuplift
North DSFSforms
Pal
myr
ide/
Sin
jar T
roug
h ge
nera
lly
cont
inuo
us e
nviro
nmen
t
Coastal margin
Oceanic
Continental areas and fragments
Very shallow marineor emerged
Deep marine
Shallow marine
South America,
Africaand
Africa-Eurasia diverge
North-South
America diverge
Suturing onN. margin;
margin shortening
Ope
ning
of E
aste
rn M
edite
rran
ean;
exa
ct ti
me
of fi
rst s
ea-f
loor
spr
eadi
ng u
ncer
tain
. E
piso
dic
reac
tivat
ion
of s
prea
ding
and
rift
ing
thro
ugho
ut M
esoz
oicRegional
uplift, tilting, and erosion
Epi
sodi
c M
esoz
oic
volc
anis
m, e
spec
ially
in L
iass
ic a
nd E
arly
Cre
tace
ous
rela
ted
to e
xten
sion